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SCS-C02 Study Guide & Reviewer

Comprehensive Study Materials & Key Concepts

AWS Certified Security - Specialty (SCS-C02) Comprehensive Study Guide

Complete Learning Path for Certification Success

Overview

This study guide provides a structured learning path from fundamentals to exam readiness for the AWS Certified Security - Specialty (SCS-C02) certification. Designed for novices, it teaches all concepts progressively while focusing exclusively on exam-relevant content. Extensive diagrams and visual aids are integrated throughout to enhance understanding and retention.

Target Audience: Complete beginners with little to no AWS security experience who need to learn everything from scratch.

Study Time: 6-10 weeks of dedicated study (2-3 hours per day)

Content Philosophy:

  • Self-sufficient: You should NOT need external resources to understand concepts
  • Comprehensive: Explains WHY and HOW, not just WHAT
  • Novice-friendly: Assumes no prior knowledge, builds up progressively
  • Example-rich: Multiple practical examples for every concept
  • Visually detailed: Extensive diagrams with detailed explanations

Exam Details

Exam Code: SCS-C02
Exam Duration: 170 minutes (2 hours 50 minutes)
Number of Questions: 65 total (50 scored + 15 unscored)
Passing Score: 750 out of 1000
Question Types:

  • Multiple choice (1 correct answer)
  • Multiple response (2+ correct answers)

Exam Domains and Weights:

  1. Threat Detection and Incident Response (14%)
  2. Security Logging and Monitoring (18%)
  3. Infrastructure Security (20%)
  4. Identity and Access Management (16%)
  5. Data Protection (18%)
  6. Management and Security Governance (14%)

Study Plan Overview

Total Time: 6-10 weeks (2-3 hours daily)

Week-by-Week Breakdown

Week 1-2: Foundations

  • Read: 01_fundamentals
  • Read: 02_domain1_threat_detection
  • Focus: Understanding AWS security basics, threat detection services
  • Practice: Complete Domain 1 practice questions
  • Goal: 70%+ on Domain 1 bundle

Week 3-4: Logging and Infrastructure

  • Read: 03_domain2_logging_monitoring
  • Read: 04_domain3_infrastructure
  • Focus: CloudTrail, CloudWatch, VPC security, network controls
  • Practice: Complete Domain 2 and 3 practice questions
  • Goal: 70%+ on Domain 2 and 3 bundles

Week 5-6: Identity and Data Protection

  • Read: 05_domain4_iam
  • Read: 06_domain5_data_protection
  • Focus: IAM policies, encryption, KMS, data lifecycle
  • Practice: Complete Domain 4 and 5 practice questions
  • Goal: 70%+ on Domain 4 and 5 bundles

Week 7-8: Governance and Integration

  • Read: 07_domain6_governance
  • Read: 08_integration
  • Focus: Organizations, Control Tower, cross-domain scenarios
  • Practice: Complete Domain 6 practice questions and service-focused bundles
  • Goal: 70%+ on all remaining bundles

Week 9: Practice and Review

  • Complete: Full Practice Test 1 (target: 65%+)
  • Review: All weak areas identified in practice test
  • Complete: Full Practice Test 2 (target: 70%+)
  • Review: Focus on question patterns and timing

Week 10: Final Preparation

  • Complete: Full Practice Test 3 (target: 75%+)
  • Read: 09_study_strategies
  • Read: 10_final_checklist
  • Review: All marked sections and critical topics
  • Final: Light review day before exam

Learning Approach

1. Read Actively

  • Don't just read passively - take notes
  • Highlight ⭐ items as must-know
  • Draw your own diagrams to reinforce concepts
  • Explain concepts out loud to yourself

2. Use the Diagrams

  • Study each diagram carefully
  • Read the detailed explanation that accompanies it
  • Try to recreate diagrams from memory
  • Use diagrams to visualize architectures during practice questions

3. Practice Regularly

  • Complete exercises after each section
  • Don't skip the self-assessment checklists
  • Use practice questions to validate understanding
  • Review incorrect answers thoroughly

4. Test Yourself

  • Use practice test bundles progressively
  • Start with domain-focused bundles
  • Move to difficulty-based bundles
  • Finish with full practice tests

5. Review and Reinforce

  • Revisit marked sections weekly
  • Create your own summary notes
  • Use the appendices as quick reference
  • Return to diagrams when concepts are unclear

Progress Tracking

Use checkboxes to track your completion:

Chapter Completion

  • Chapter 0: Fundamentals (01_fundamentals)
  • Chapter 1: Threat Detection (02_domain1_threat_detection)
  • Chapter 2: Logging & Monitoring (03_domain2_logging_monitoring)
  • Chapter 3: Infrastructure Security (04_domain3_infrastructure)
  • Chapter 4: Identity & Access Management (05_domain4_iam)
  • Chapter 5: Data Protection (06_domain5_data_protection)
  • Chapter 6: Governance (07_domain6_governance)
  • Chapter 7: Integration (08_integration)
  • Chapter 8: Study Strategies (09_study_strategies)
  • Chapter 9: Final Checklist (10_final_checklist)

Practice Test Completion

  • Domain 1 Bundle 1 (Score: ___%)
  • Domain 1 Bundle 2 (Score: ___%)
  • Domain 2 Bundle 1 (Score: ___%)
  • Domain 2 Bundle 2 (Score: ___%)
  • Domain 3 Bundle 1 (Score: ___%)
  • Domain 3 Bundle 2 (Score: ___%)
  • Domain 4 Bundle 1 (Score: ___%)
  • Domain 4 Bundle 2 (Score: ___%)
  • Domain 5 Bundle 1 (Score: ___%)
  • Domain 5 Bundle 2 (Score: ___%)
  • Domain 6 Bundle 1 (Score: ___%)
  • Domain 6 Bundle 2 (Score: ___%)
  • Full Practice Test 1 (Score: ___%)
  • Full Practice Test 2 (Score: ___%)
  • Full Practice Test 3 (Score: ___%)

Readiness Checklist

  • Scoring 75%+ on all practice tests
  • Can explain key concepts without notes
  • Recognize question patterns instantly
  • Make decisions quickly using frameworks
  • Completed final week checklist

Legend

Throughout this study guide, you'll see these visual markers:

  • Must Know: Critical information for the exam - memorize this
  • 💡 Tip: Helpful insight or shortcut to remember concepts
  • ⚠️ Warning: Common mistake to avoid - many test-takers get this wrong
  • 🔗 Connection: Related to other topics - shows how concepts link together
  • 📝 Practice: Hands-on exercise to reinforce learning
  • 🎯 Exam Focus: Frequently tested on the exam - pay special attention
  • 📊 Diagram: Visual representation available - study the diagram carefully

How to Navigate This Guide

For Complete Beginners

  1. Start with Chapter 0 (Fundamentals) - don't skip this
  2. Read chapters sequentially (1 → 2 → 3 → 4 → 5 → 6 → 7)
  3. Spend extra time on diagrams - they're your best learning tool
  4. Complete all self-assessment checklists before moving forward
  5. Don't rush - understanding is more important than speed

For Those With Some AWS Experience

  1. Skim Chapter 0 (Fundamentals) to identify gaps
  2. Focus on chapters aligned with your weak domains
  3. Use practice tests to identify specific areas needing study
  4. Jump to relevant sections using the appendices as reference
  5. Prioritize ⭐ Must Know items and 🎯 Exam Focus sections

For Visual Learners

  1. Study all diagrams before reading the text
  2. Try to understand the flow from diagrams alone
  3. Then read the detailed explanations
  4. Create your own variations of the diagrams
  5. Use diagrams to answer practice questions

For Those Short on Time

  1. Focus on ⭐ Must Know and 🎯 Exam Focus items
  2. Study all diagrams thoroughly (they condense information)
  3. Complete at least 3 full practice tests
  4. Review Chapter 8 (Study Strategies) early
  5. Use Chapter 9 (Final Checklist) in your last week

Study Tips for Success

Time Management

  • Consistency beats intensity: 2 hours daily is better than 14 hours on weekends
  • Use dead time: Review diagrams on your phone during commutes
  • Set milestones: Complete one chapter per week minimum
  • Track progress: Update your checklist daily for motivation

Active Learning Techniques

  1. Teach Someone: Explain concepts to a friend or colleague
  2. Draw Diagrams: Recreate architectures from memory
  3. Write Scenarios: Create your own security scenarios
  4. Compare Options: Use comparison tables to understand differences

Memory Techniques

  • Mnemonics: Create acronyms for lists (we provide many)
  • Visual Patterns: Associate services with their icons/colors
  • Story Method: Create stories linking related concepts
  • Spaced Repetition: Review material at increasing intervals

Avoiding Burnout

  • Take breaks every 45-60 minutes
  • Study different domains on different days
  • Mix reading with practice questions
  • Reward yourself for completing milestones
  • Don't study the day before the exam

Prerequisites

Before starting this study guide, you should have:

Required:

  • Basic understanding of cloud computing concepts
  • Familiarity with AWS console navigation
  • Understanding of basic networking (IP addresses, ports, protocols)
  • Basic Linux/Windows command line knowledge

Recommended (but not required):

  • 1-2 years of AWS experience (we'll teach you if you don't have this)
  • AWS Certified Solutions Architect - Associate (helpful but not necessary)
  • Experience with at least one programming language (for understanding code examples)

If you're missing prerequisites: Chapter 0 (Fundamentals) provides a primer on essential concepts. You may need to spend extra time on this chapter.

What This Guide Covers

All exam domains in comprehensive detail
120-200 visual diagrams for complex concepts
Real-world scenarios based on actual security challenges
Step-by-step explanations of how services work
Decision frameworks for choosing between options
Troubleshooting guides for common issues
Best practices aligned with AWS recommendations
Practice integration with test bundles
Study strategies and test-taking techniques

What This Guide Does NOT Cover

Non-security AWS services (unless relevant to security)
Programming language tutorials (we show code examples but don't teach languages)
Hands-on lab instructions (we explain concepts, you practice separately)
Regulatory compliance details (we cover AWS tools, not legal requirements)
Third-party security tools (focus is on native AWS services)

Getting Help

If You're Stuck on a Concept

  1. Re-read the section slowly
  2. Study the related diagram carefully
  3. Look up the concept in the appendices
  4. Try a practice question on that topic
  5. Move on and return later with fresh perspective

If Practice Test Scores Are Low

  1. Review the explanations for incorrect answers
  2. Identify patterns in your mistakes
  3. Return to relevant study guide chapters
  4. Focus on ⭐ Must Know items in weak areas
  5. Complete domain-focused bundles for weak domains

If You're Running Out of Time

  1. Prioritize high-weight domains (3, 2, 5)
  2. Focus on ⭐ Must Know items only
  3. Study diagrams intensively (they're efficient)
  4. Complete at least 2 full practice tests
  5. Review Chapter 9 (Final Checklist) thoroughly

Final Words Before You Begin

This certification is challenging but achievable with dedicated study. The AWS Certified Security - Specialty validates deep knowledge of AWS security services and best practices. It's respected in the industry and can significantly advance your career.

Remember:

  • Quality over speed: Understanding deeply is better than covering material quickly
  • Practice is essential: Reading alone won't prepare you - do the practice tests
  • Diagrams are powerful: Visual learning accelerates comprehension
  • Consistency wins: Regular study beats cramming
  • You can do this: Thousands have passed using structured study approaches like this

Ready to begin? Turn to Chapter 0 (01_fundamentals) and start your journey to AWS Security Specialty certification!


Study Guide Version: 1.0
Last Updated: October 2025
Exam Version: SCS-C02
Total Word Count: 60,000-120,000 words
Total Diagrams: 120-200 Mermaid diagrams
Estimated Study Time: 6-10 weeks (2-3 hours daily)

Good luck on your certification journey! 🎯


Chapter 0: Essential Background and Prerequisites

What You Need to Know First

This certification assumes you understand certain foundational concepts. Before diving into AWS security services, let's ensure you have the necessary background knowledge.

Prerequisites Checklist

  • Cloud Computing Basics - Understanding of what cloud computing is and its benefits
  • AWS Core Services - Familiarity with EC2, S3, VPC, IAM at a basic level
  • Networking Fundamentals - IP addresses, subnets, routing, DNS, ports, protocols
  • Security Concepts - Confidentiality, integrity, availability (CIA triad)
  • Linux/Windows Basics - Command line navigation, file permissions
  • JSON Format - Ability to read and understand JSON documents (used in policies)

If you're missing any: Don't worry! This chapter will provide a primer on essential concepts. You may need to spend extra time here, and that's perfectly fine.

Core Concepts Foundation

The AWS Shared Responsibility Model

What it is: A security framework that defines which security responsibilities belong to AWS and which belong to you (the customer).

Why it matters: This is THE foundational concept for AWS security. Every security decision you make must consider who is responsible for what. The exam tests this concept extensively.

Real-world analogy: Think of renting an apartment. The building owner (AWS) is responsible for the physical security of the building - locks on the main entrance, security cameras, structural integrity. You (the tenant) are responsible for locking your apartment door, not giving your keys to strangers, and securing your belongings inside. Both parties have distinct but complementary responsibilities.

How it works (Detailed breakdown):

  1. AWS Responsibility - "Security OF the Cloud":

    • AWS manages the physical infrastructure: data centers, servers, networking equipment, storage devices
    • AWS secures the hypervisor layer that runs virtual machines
    • AWS maintains the physical network infrastructure and edge locations
    • AWS ensures the availability and durability of their services
    • AWS handles physical access controls to data centers
    • AWS manages the underlying software for managed services
  2. Customer Responsibility - "Security IN the Cloud":

    • You configure security groups, network ACLs, and firewall rules
    • You manage IAM users, roles, and policies
    • You encrypt your data (at rest and in transit)
    • You patch and update your operating systems and applications
    • You configure logging and monitoring
    • You implement backup and disaster recovery strategies
    • You manage application-level security
  3. Shared Controls (Both parties have responsibilities):

    • Patch Management: AWS patches infrastructure; you patch your OS and applications
    • Configuration Management: AWS configures infrastructure; you configure your resources
    • Awareness & Training: AWS trains their staff; you train your users

📊 Shared Responsibility Model Diagram:

graph TB
    subgraph "Customer Responsibility - Security IN the Cloud"
        A[Customer Data]
        B[Application Security]
        C[Identity & Access Management]
        D[Operating System Patching]
        E[Network Configuration]
        F[Firewall Configuration]
        G[Encryption - Client Side]
    end
    
    subgraph "Shared Controls"
        H[Patch Management]
        I[Configuration Management]
        J[Awareness & Training]
    end
    
    subgraph "AWS Responsibility - Security OF the Cloud"
        K[Physical Security]
        L[Infrastructure Hardware]
        M[Network Infrastructure]
        N[Virtualization Layer]
        O[Managed Service Security]
        P[Global Infrastructure]
    end
    
    A --> B --> C --> D --> E --> F --> G
    G --> H
    H --> I --> J
    J --> K
    K --> L --> M --> N --> O --> P
    
    style A fill:#ffcdd2
    style B fill:#ffcdd2
    style C fill:#ffcdd2
    style D fill:#ffcdd2
    style E fill:#ffcdd2
    style F fill:#ffcdd2
    style G fill:#ffcdd2
    style H fill:#fff9c4
    style I fill:#fff9c4
    style J fill:#fff9c4
    style K fill:#c8e6c9
    style L fill:#c8e6c9
    style M fill:#c8e6c9
    style N fill:#c8e6c9
    style O fill:#c8e6c9
    style P fill:#c8e6c9

See: diagrams/01_fundamentals_shared_responsibility.mmd

Diagram Explanation (Detailed):

The diagram shows three distinct layers of responsibility in AWS security. At the top (red), customer responsibilities include everything you directly control: your data, applications, IAM configurations, OS patches, network rules, and client-side encryption. These are YOUR security tasks - AWS cannot do them for you. In the middle (yellow), shared controls represent areas where both AWS and the customer have responsibilities, but for different aspects. For example, in patch management, AWS patches the underlying infrastructure and managed service components, while you must patch your EC2 operating systems and applications. At the bottom (green), AWS responsibilities cover the physical and infrastructure layers: securing data centers, maintaining hardware, managing the network backbone, securing the hypervisor, and ensuring the global infrastructure is resilient. The flow from top to bottom shows how security builds from customer-managed layers down through shared controls to AWS-managed infrastructure. Understanding where your responsibilities end and AWS's begin is critical for exam success and real-world security implementation.

Must Know (Critical Facts):

  • AWS manages security OF the cloud (infrastructure, hardware, facilities, managed services)
  • You manage security IN the cloud (data, applications, IAM, OS, network config, encryption)
  • Responsibility varies by service type: IaaS (you do more), PaaS (shared), SaaS (AWS does more)
  • You are ALWAYS responsible for your data - AWS never accesses your data without permission
  • Encryption is YOUR responsibility - AWS provides tools, but you must enable and configure them

Detailed Example 1: Amazon EC2 (Infrastructure as a Service)

You launch an EC2 instance to run a web application. Here's how responsibilities are divided:

AWS Responsibilities:

  • Securing the physical server hardware in the data center
  • Maintaining the hypervisor that runs your virtual machine
  • Ensuring the physical network infrastructure is secure and available
  • Protecting against DDoS attacks at the infrastructure level
  • Maintaining the underlying storage systems

Your Responsibilities:

  • Choosing the right security group rules (which ports to open)
  • Patching the operating system (Windows updates, Linux package updates)
  • Installing and configuring a host-based firewall if needed
  • Encrypting the EBS volumes attached to the instance
  • Managing SSH keys or RDP passwords for access
  • Installing and updating application software
  • Configuring CloudWatch monitoring and logging
  • Implementing backup strategies for your data

What happens if there's a breach: If someone hacks into your EC2 instance because you left SSH open to the internet (0.0.0.0/0) with a weak password, that's YOUR responsibility. If AWS's physical data center is breached, that's AWS's responsibility.

Detailed Example 2: Amazon S3 (Platform as a Service)

You store customer documents in an S3 bucket. Responsibilities:

AWS Responsibilities:

  • Ensuring 99.999999999% (11 nines) durability of your objects
  • Replicating data across multiple facilities automatically
  • Securing the physical storage infrastructure
  • Maintaining the S3 service API and infrastructure
  • Protecting against infrastructure-level threats

Your Responsibilities:

  • Configuring bucket policies to control who can access your data
  • Enabling encryption at rest (S3-SSE, KMS, or client-side)
  • Enabling encryption in transit (HTTPS enforcement)
  • Configuring S3 Block Public Access to prevent accidental exposure
  • Enabling versioning and MFA Delete for data protection
  • Setting up logging (S3 access logs, CloudTrail)
  • Implementing lifecycle policies for data retention
  • Classifying and protecting sensitive data

What happens if data is exposed: If you accidentally make your S3 bucket public and sensitive data leaks, that's YOUR responsibility. AWS provides tools (S3 Block Public Access, bucket policies) but you must configure them correctly.

Detailed Example 3: Amazon RDS (More Managed Service)

You use RDS for a MySQL database. Responsibilities shift more toward AWS:

AWS Responsibilities:

  • Patching the database engine (MySQL, PostgreSQL, etc.)
  • Performing automated backups
  • Maintaining the underlying infrastructure
  • Providing Multi-AZ replication for high availability
  • Managing the database software installation

Your Responsibilities:

  • Configuring security groups to control network access
  • Managing database users and permissions
  • Enabling encryption at rest when creating the database
  • Enabling encryption in transit (SSL/TLS connections)
  • Configuring parameter groups for security settings
  • Monitoring database performance and security events
  • Implementing application-level access controls
  • Protecting database credentials (use Secrets Manager)

Key Insight: As services become more managed (EC2 → RDS → Lambda → S3), AWS takes on more responsibility, but you ALWAYS remain responsible for data, access control, and encryption configuration.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "AWS is responsible for security, so I don't need to worry about it"

    • Why it's wrong: AWS secures the infrastructure, but YOU must secure your configurations, data, and applications
    • Correct understanding: Security is a shared responsibility - both parties must fulfill their obligations
  • Mistake 2: "If I use a managed service like RDS, AWS handles all security"

    • Why it's wrong: AWS manages the infrastructure and database patching, but you still configure access controls, encryption, and network security
    • Correct understanding: Managed services reduce your operational burden but don't eliminate your security responsibilities
  • Mistake 3: "AWS can access my data anytime they want"

    • Why it's wrong: AWS has strict policies and technical controls preventing unauthorized access to customer data
    • Correct understanding: AWS personnel cannot access your data without your explicit permission (except in rare legal circumstances)

🔗 Connections to Other Topics:

  • Relates to IAM because: You're responsible for managing identities and access controls
  • Builds on Encryption by: You must enable and configure encryption for your data
  • Often used with Compliance to: Understand which controls you must implement vs. which AWS provides

The CIA Triad - Core Security Principles

What it is: The three fundamental principles of information security: Confidentiality, Integrity, and Availability.

Why it exists: Every security control, service, and decision in AWS (and security in general) aims to protect one or more of these three principles. Understanding the CIA triad helps you evaluate security solutions and answer exam questions.

Real-world analogy: Think of a bank vault:

  • Confidentiality: Only authorized people can see what's inside (access controls, locks)
  • Integrity: The contents haven't been tampered with (seals, audit trails)
  • Availability: You can access your valuables when you need them (vault is open during business hours)

How it works (Detailed step-by-step):

  1. Confidentiality - Keeping Secrets Secret:

    • Definition: Ensuring that information is accessible only to those authorized to access it
    • AWS Implementation: Encryption (KMS, S3 encryption), IAM policies, security groups, private subnets, VPC endpoints
    • Threats: Unauthorized access, data breaches, eavesdropping, social engineering
    • Controls: Encryption at rest, encryption in transit, least privilege access, MFA, network segmentation
  2. Integrity - Preventing Unauthorized Changes:

    • Definition: Ensuring that information is accurate, complete, and hasn't been tampered with
    • AWS Implementation: S3 Object Lock, Glacier Vault Lock, CloudTrail log file validation, versioning, checksums
    • Threats: Data tampering, unauthorized modifications, malware, insider threats
    • Controls: Versioning, immutable storage, digital signatures, hash verification, audit logging
  3. Availability - Ensuring Access When Needed:

    • Definition: Ensuring that authorized users can access information and resources when needed
    • AWS Implementation: Multi-AZ deployments, Auto Scaling, CloudFront, Route 53, backups, DDoS protection (Shield)
    • Threats: DDoS attacks, hardware failures, natural disasters, misconfigurations, resource exhaustion
    • Controls: Redundancy, load balancing, auto-scaling, backups, disaster recovery, DDoS mitigation

📊 CIA Triad Diagram:

graph TD
    A[CIA Triad - Information Security]
    
    A --> B[Confidentiality]
    A --> C[Integrity]
    A --> D[Availability]
    
    B --> B1[Encryption at Rest]
    B --> B2[Encryption in Transit]
    B --> B3[Access Controls - IAM]
    B --> B4[Network Segmentation]
    B --> B5[MFA]
    
    C --> C1[Versioning]
    C --> C2[Object Lock]
    C --> C3[Audit Logging]
    C --> C4[Hash Verification]
    C --> C5[Digital Signatures]
    
    D --> D1[Multi-AZ Deployment]
    D --> D2[Auto Scaling]
    D --> D3[Load Balancing]
    D --> D4[Backups]
    D --> D5[DDoS Protection]
    
    style A fill:#e1f5fe
    style B fill:#ffcdd2
    style C fill:#fff9c4
    style D fill:#c8e6c9

See: diagrams/01_fundamentals_cia_triad.mmd

Diagram Explanation (Detailed):

The CIA Triad diagram shows the three pillars of information security and how AWS services map to each principle. At the center is the CIA Triad concept, which branches into three equal components. Confidentiality (red) focuses on keeping data private through encryption (both at rest using KMS and in transit using TLS), access controls via IAM policies, network segmentation using VPCs and security groups, and multi-factor authentication. Integrity (yellow) ensures data hasn't been tampered with through versioning systems, immutable storage like S3 Object Lock, comprehensive audit logging with CloudTrail, hash verification for data validation, and digital signatures for authenticity. Availability (green) guarantees systems remain accessible through Multi-AZ deployments for redundancy, Auto Scaling to handle load, load balancing to distribute traffic, regular backups for recovery, and DDoS protection via AWS Shield. Every AWS security service and feature you'll learn in this guide ultimately serves to protect one or more of these three principles. When answering exam questions, ask yourself: "Which part of the CIA triad does this protect?"

Must Know (Critical Facts):

  • All three principles are equally important - you can't sacrifice one for another
  • AWS services often protect multiple CIA principles - for example, encryption protects both confidentiality and integrity
  • Exam questions often test which principle is being protected - identify whether a scenario needs confidentiality, integrity, or availability
  • Trade-offs exist: Extreme availability measures might impact confidentiality (more access points = more attack surface)
  • Compliance frameworks (PCI-DSS, HIPAA, SOC 2) are built around protecting the CIA triad

Detailed Example 1: Protecting Customer Credit Card Data (Confidentiality Focus)

Scenario: An e-commerce company stores customer credit card information in a database.

Confidentiality Measures:

  • Encrypt the database at rest using AWS KMS with customer-managed keys
  • Encrypt all data in transit using TLS 1.2 or higher
  • Store the database in a private subnet with no internet access
  • Use IAM policies to restrict database access to only the payment processing application
  • Implement security groups allowing only specific application servers to connect
  • Enable MFA for any human access to the database
  • Use VPC endpoints for AWS service access (no internet gateway)
  • Tokenize credit card numbers so the actual numbers aren't stored

Why these work: Each control reduces the risk of unauthorized access. Even if one control fails (e.g., someone gains network access), other layers (encryption, IAM) still protect the data.

Detailed Example 2: Ensuring Financial Records Aren't Tampered With (Integrity Focus)

Scenario: A financial services company must prove their transaction logs haven't been altered for regulatory compliance.

Integrity Measures:

  • Store logs in S3 with Object Lock in Compliance mode (cannot be deleted or modified)
  • Enable S3 Versioning to track any changes
  • Use CloudTrail log file validation to detect tampering
  • Implement S3 bucket policies preventing deletion or modification
  • Enable MFA Delete requiring two-factor authentication to delete objects
  • Use AWS Config to monitor for configuration changes
  • Store cryptographic hashes of log files for verification
  • Replicate logs to a separate AWS account for additional protection

Why these work: These controls create an immutable audit trail. Even administrators cannot modify or delete logs once written, providing proof of integrity for auditors.

Detailed Example 3: Keeping a Website Available During Traffic Spikes (Availability Focus)

Scenario: An online retailer needs their website to remain available during Black Friday sales when traffic increases 10x.

Availability Measures:

  • Deploy application across multiple Availability Zones (Multi-AZ)
  • Use Application Load Balancer to distribute traffic across instances
  • Implement Auto Scaling to automatically add capacity during spikes
  • Use CloudFront CDN to cache static content closer to users
  • Enable AWS Shield Standard for DDoS protection (free)
  • Upgrade to Shield Advanced for large-scale DDoS protection
  • Use Route 53 health checks to route traffic away from unhealthy resources
  • Implement database read replicas to distribute read traffic
  • Set up automated backups for quick recovery if needed

Why these work: These controls eliminate single points of failure and automatically scale to handle increased demand. If one AZ fails, traffic routes to healthy AZs. If traffic spikes, Auto Scaling adds capacity.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Encryption solves all security problems"

    • Why it's wrong: Encryption primarily protects confidentiality and some aspects of integrity, but doesn't help with availability
    • Correct understanding: Encryption is one tool in a comprehensive security strategy that must address all three CIA principles
  • Mistake 2: "High availability is more important than security"

    • Why it's wrong: Making systems highly available by opening them to the internet without proper controls sacrifices confidentiality
    • Correct understanding: All three principles must be balanced - availability shouldn't come at the cost of confidentiality or integrity
  • Mistake 3: "Backups protect integrity"

    • Why it's wrong: Backups primarily protect availability (you can restore if data is lost), not integrity (they don't prevent tampering)
    • Correct understanding: Backups are an availability control; integrity requires versioning, immutability, and audit trails

🔗 Connections to Other Topics:

  • Relates to Encryption because: Encryption is the primary tool for protecting confidentiality
  • Builds on Multi-AZ by: Multi-AZ deployments are key availability controls
  • Often used with Incident Response to: When incidents occur, determine which CIA principle was compromised

AWS Regions, Availability Zones, and Edge Locations

What it is: AWS's global infrastructure is organized into Regions (geographic areas), Availability Zones (isolated data centers within regions), and Edge Locations (CDN endpoints).

Why it exists: This infrastructure design enables high availability, fault tolerance, low latency, and compliance with data residency requirements. Understanding this architecture is essential for designing secure, resilient systems.

Real-world analogy: Think of a global retail chain:

  • Regions are like countries where the company operates (US, Europe, Asia)
  • Availability Zones are like multiple stores in different neighborhoods of the same city (if one store has a problem, customers can go to another)
  • Edge Locations are like pickup points or kiosks closer to customers for faster service

How it works (Detailed step-by-step):

  1. AWS Regions (Geographic Areas):

    • A Region is a physical location with multiple Availability Zones
    • Each Region is completely independent and isolated from other Regions
    • Data doesn't leave a Region unless you explicitly configure it to
    • Examples: us-east-1 (N. Virginia), eu-west-1 (Ireland), ap-southeast-1 (Singapore)
    • Choose Regions based on: latency to users, data residency requirements, service availability, cost
  2. Availability Zones (AZs) (Isolated Data Centers):

    • Each AZ is one or more discrete data centers with redundant power, networking, and connectivity
    • AZs within a Region are connected via low-latency, high-bandwidth private fiber
    • AZs are physically separated (different buildings, flood plains, power grids)
    • Typical Region has 3-6 AZs (e.g., us-east-1 has 6 AZs: us-east-1a through us-east-1f)
    • Deploy resources across multiple AZs for high availability
  3. Edge Locations (CDN Endpoints):

    • Edge Locations are endpoints for CloudFront (AWS's CDN)
    • There are 400+ Edge Locations globally (more than Regions)
    • Cache content closer to end users for lower latency
    • Also used by Route 53, AWS Shield, and AWS WAF
    • Not full AWS Regions - limited services available

📊 AWS Global Infrastructure Diagram:

graph TB
    subgraph "AWS Global Infrastructure"
        subgraph "Region: us-east-1 (N. Virginia)"
            subgraph "AZ: us-east-1a"
                A1[Data Center 1]
                A2[Data Center 2]
            end
            subgraph "AZ: us-east-1b"
                B1[Data Center 3]
                B2[Data Center 4]
            end
            subgraph "AZ: us-east-1c"
                C1[Data Center 5]
            end
        end
        
        subgraph "Region: eu-west-1 (Ireland)"
            subgraph "AZ: eu-west-1a"
                D1[Data Center 6]
            end
            subgraph "AZ: eu-west-1b"
                E1[Data Center 7]
            end
            subgraph "AZ: eu-west-1c"
                F1[Data Center 8]
            end
        end
        
        G[Edge Location - New York]
        H[Edge Location - London]
        I[Edge Location - Tokyo]
    end
    
    A1 -.Low Latency Link.-> B1
    B1 -.Low Latency Link.-> C1
    
    D1 -.Low Latency Link.-> E1
    E1 -.Low Latency Link.-> F1
    
    A1 -.Cross-Region Replication.-> D1
    
    G -.CloudFront CDN.-> A1
    H -.CloudFront CDN.-> D1
    I -.CloudFront CDN.-> A1
    
    style A1 fill:#c8e6c9
    style A2 fill:#c8e6c9
    style B1 fill:#c8e6c9
    style B2 fill:#c8e6c9
    style C1 fill:#c8e6c9
    style D1 fill:#bbdefb
    style E1 fill:#bbdefb
    style F1 fill:#bbdefb
    style G fill:#fff9c4
    style H fill:#fff9c4
    style I fill:#fff9c4

See: diagrams/01_fundamentals_global_infrastructure.mmd

Diagram Explanation (Detailed):

The AWS Global Infrastructure diagram illustrates how AWS organizes its worldwide data center network. At the top level, we see two Regions: us-east-1 (N. Virginia) shown in green and eu-west-1 (Ireland) shown in blue. Each Region contains multiple Availability Zones (AZs), which are physically separated but connected via low-latency private fiber links (shown as dotted lines). Within us-east-1, there are three AZs (1a, 1b, 1c), with some AZs containing multiple discrete data centers for additional redundancy. The AZs are interconnected with high-bandwidth, low-latency links allowing synchronous replication between them. Similarly, eu-west-1 has three AZs with the same interconnection pattern. The Regions themselves are completely isolated - data doesn't flow between them unless you explicitly configure cross-region replication (shown as the dotted line between us-east-1a and eu-west-1a). At the bottom, Edge Locations (yellow) in New York, London, and Tokyo connect to the nearest Region via CloudFront CDN, caching content closer to end users for faster delivery. This architecture enables you to design highly available applications by deploying across multiple AZs within a Region, and globally distributed applications by deploying across multiple Regions with Edge Location caching.

Must Know (Critical Facts):

  • Regions are completely isolated - data doesn't leave a Region unless you configure it
  • AZs within a Region are connected - low latency (<2ms typically) allows synchronous replication
  • Deploy across multiple AZs for high availability - if one AZ fails, others continue operating
  • Each AZ has independent power, cooling, and networking - no single point of failure
  • Not all services are available in all Regions - check service availability before choosing a Region
  • Data residency compliance - choose Regions based on where data must legally reside

When to use (Comprehensive):

  • Use Multi-AZ when: You need high availability and can tolerate slightly higher costs (typically 2x for redundancy)
  • Use Multi-Region when: You need disaster recovery, global low latency, or data residency compliance
  • Use Edge Locations when: You need to cache static content (images, videos, files) closer to users
  • Don't use Multi-AZ when: Cost is the only consideration and downtime is acceptable (rare)
  • Don't use Multi-Region when: You only serve users in one geographic area and don't need DR

Detailed Example 1: High Availability Web Application (Multi-AZ)

Scenario: You're building a web application that must remain available even if an entire data center fails.

Architecture:

  1. Deploy Application Load Balancer across 3 AZs (us-east-1a, 1b, 1c)
  2. Launch EC2 instances in Auto Scaling groups across all 3 AZs
  3. Use RDS Multi-AZ for the database (primary in 1a, standby in 1b)
  4. Store static assets in S3 (automatically replicated across AZs)
  5. Use CloudFront to cache content at Edge Locations

What happens during an AZ failure:

  • If us-east-1a fails completely (power outage, network issue):
    • Load Balancer stops sending traffic to instances in 1a
    • Instances in 1b and 1c continue serving requests
    • RDS automatically fails over to standby in 1b (1-2 minutes)
    • Users experience minimal disruption (brief connection errors during failover)
    • Auto Scaling launches replacement instances in healthy AZs

Why this works: No single AZ failure can take down the application. The Load Balancer and Auto Scaling automatically route around failures.

Detailed Example 2: Global Application with Data Residency (Multi-Region)

Scenario: You operate in both the US and EU, and EU data must remain in EU due to GDPR.

Architecture:

  1. Deploy complete application stack in us-east-1 for US users
  2. Deploy complete application stack in eu-west-1 for EU users
  3. Use Route 53 geolocation routing to direct users to nearest Region
  4. Store US customer data in us-east-1 S3 buckets
  5. Store EU customer data in eu-west-1 S3 buckets
  6. Use separate RDS instances in each Region (no cross-region replication of customer data)
  7. Replicate application code and configuration across Regions

What happens:

  • EU users connect to eu-west-1, their data never leaves the EU Region
  • US users connect to us-east-1, their data stays in the US
  • If us-east-1 fails, US users can be routed to eu-west-1 (but EU data stays in EU)
  • Compliance requirements are met because data residency is enforced

Why this works: Complete Regional isolation ensures data residency compliance while providing low latency to users in each geography.

Detailed Example 3: Content Delivery with Edge Locations (CloudFront)

Scenario: You have a video streaming service with users worldwide, and videos are stored in S3 in us-east-1.

Architecture:

  1. Store video files in S3 bucket in us-east-1
  2. Create CloudFront distribution with S3 as origin
  3. CloudFront automatically caches content at 400+ Edge Locations
  4. Users connect to nearest Edge Location

What happens when a user in Tokyo requests a video:

  1. User's request goes to Tokyo Edge Location (low latency)
  2. If video is cached at Edge Location, it's served immediately (cache hit)
  3. If video is not cached, Edge Location fetches it from S3 in us-east-1 (cache miss)
  4. Edge Location caches the video for future requests
  5. Subsequent users in Tokyo get the cached version (fast)

Why this works: Edge Locations cache content close to users, reducing latency from ~200ms (Tokyo to Virginia) to ~5ms (Tokyo to Tokyo Edge Location).

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Deploying in one AZ is enough for high availability"

    • Why it's wrong: A single AZ can fail (power outage, network issue, natural disaster)
    • Correct understanding: Always deploy across at least 2 AZs, preferably 3, for true high availability
  • Mistake 2: "All AWS services are available in all Regions"

    • Why it's wrong: New services often launch in us-east-1 first and gradually expand to other Regions
    • Correct understanding: Always check service availability in your target Region before designing architecture
  • Mistake 3: "Edge Locations are the same as Availability Zones"

    • Why it's wrong: Edge Locations only support CloudFront, Route 53, WAF, and Shield - not full AWS services
    • Correct understanding: Edge Locations are CDN endpoints for caching, not full data centers

🔗 Connections to Other Topics:

  • Relates to High Availability because: Multi-AZ deployments are the foundation of HA architectures
  • Builds on Disaster Recovery by: Multi-Region deployments enable DR strategies
  • Often used with Compliance to: Data residency requirements dictate Region selection

Networking Fundamentals for AWS Security

What it is: Basic networking concepts that underpin AWS security controls like security groups, NACLs, and VPCs.

Why it exists: You cannot secure what you don't understand. AWS security heavily relies on network controls, so understanding IP addresses, ports, protocols, and routing is essential.

Real-world analogy: Think of networking like a postal system:

  • IP addresses are like street addresses (identify destinations)
  • Ports are like apartment numbers (identify specific services at an address)
  • Protocols are like delivery methods (regular mail vs. certified mail)
  • Subnets are like neighborhoods (groups of related addresses)

How it works (Detailed step-by-step):

  1. IP Addresses and CIDR Notation:

    • IPv4 address: 32-bit number written as four octets (e.g., 192.168.1.10)
    • CIDR notation: IP address + subnet mask (e.g., 10.0.0.0/16)
    • /16 means: First 16 bits are network, last 16 bits are hosts (65,536 addresses)
    • /24 means: First 24 bits are network, last 8 bits are hosts (256 addresses)
    • /32 means: Exact single IP address (1 address)
    • Private IP ranges: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 (not routable on internet)
  2. Ports and Protocols:

    • Port: A number (0-65535) identifying a specific service on a host
    • Common ports: 22 (SSH), 80 (HTTP), 443 (HTTPS), 3306 (MySQL), 5432 (PostgreSQL)
    • TCP: Connection-oriented, reliable, used for web traffic, databases, SSH
    • UDP: Connectionless, faster but less reliable, used for DNS, streaming
    • ICMP: Used for ping, traceroute, network diagnostics
  3. Subnets and Routing:

    • Subnet: A logical subdivision of an IP network
    • Public subnet: Has route to Internet Gateway (resources can reach internet)
    • Private subnet: No route to Internet Gateway (resources isolated from internet)
    • Route table: Defines where network traffic is directed
    • Default route (0.0.0.0/0): Matches all traffic not matched by specific routes

Must Know (Critical Facts):

  • 0.0.0.0/0 means "anywhere on the internet" - opening ports to this is usually dangerous
  • Security groups are stateful - if you allow inbound, outbound response is automatic
  • NACLs are stateless - you must explicitly allow both inbound and outbound
  • Smaller CIDR number = larger network (/16 is bigger than /24)
  • Common ports must be memorized - SSH (22), HTTP (80), HTTPS (443), RDP (3389)

Detailed Example 1: Understanding CIDR Blocks

Let's break down 10.0.0.0/16:

  • Network portion: 10.0 (first 16 bits)
  • Host portion: 0.0 (last 16 bits)
  • Total addresses: 2^16 = 65,536 addresses
  • Usable range: 10.0.0.0 to 10.0.255.255
  • AWS reserves: First 4 and last 1 IP in each subnet

If you create a VPC with 10.0.0.0/16, you can subdivide it:

  • Public subnet: 10.0.1.0/24 (256 addresses, 251 usable)
  • Private subnet: 10.0.2.0/24 (256 addresses, 251 usable)
  • Database subnet: 10.0.3.0/24 (256 addresses, 251 usable)

Detailed Example 2: Security Group Rules

You have a web server that needs to accept HTTPS traffic from anywhere and SSH from your office:

Inbound Rules:

  • Type: HTTPS, Protocol: TCP, Port: 443, Source: 0.0.0.0/0 (anywhere)
  • Type: SSH, Protocol: TCP, Port: 22, Source: 203.0.113.0/24 (your office IP range)

Outbound Rules:

  • Type: All traffic, Protocol: All, Port: All, Destination: 0.0.0.0/0 (default, allows responses)

What this means:

  • Anyone on the internet can connect to port 443 (HTTPS)
  • Only your office network can connect to port 22 (SSH)
  • The server can initiate outbound connections to anywhere
  • Because security groups are stateful, responses to inbound requests are automatically allowed

Detailed Example 3: Public vs. Private Subnets

Public Subnet (10.0.1.0/24):

  • Route table has: 10.0.0.0/16 → local, 0.0.0.0/0 → Internet Gateway
  • Resources can reach the internet and be reached from the internet (if security group allows)
  • Use for: Load balancers, NAT gateways, bastion hosts

Private Subnet (10.0.2.0/24):

  • Route table has: 10.0.0.0/16 → local, 0.0.0.0/0 → NAT Gateway (in public subnet)
  • Resources can reach the internet (via NAT) but cannot be reached from the internet
  • Use for: Application servers, databases, internal services

Why this matters: Private subnets provide an additional security layer. Even if someone compromises your application, they can't directly access databases in private subnets from the internet.

JSON and Policy Documents

What it is: JSON (JavaScript Object Notation) is the format used for IAM policies, resource policies, and many AWS configurations.

Why it exists: AWS needs a structured, machine-readable format for defining permissions and configurations. JSON is human-readable, widely supported, and flexible.

Real-world analogy: Think of JSON like a form with labeled fields:

  • Keys are like field labels ("Name:", "Address:")
  • Values are like what you fill in ("John Smith", "123 Main St")
  • Objects are like sections of the form (Personal Info, Contact Info)
  • Arrays are like lists (multiple phone numbers, multiple addresses)

How it works (Detailed step-by-step):

  1. Basic JSON Structure:

    • Objects: Enclosed in curly braces { }
    • Arrays: Enclosed in square brackets [ ]
    • Key-value pairs: "key": "value"
    • Data types: Strings ("text"), Numbers (123), Booleans (true/false), Null (null)
  2. IAM Policy Structure:

    • Version: Policy language version (always "2012-10-17")
    • Statement: Array of permission statements
    • Effect: "Allow" or "Deny"
    • Action: What actions are allowed/denied
    • Resource: Which resources the actions apply to
    • Condition: Optional conditions for when the policy applies

Example IAM Policy:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetObject",
        "s3:PutObject"
      ],
      "Resource": "arn:aws:s3:::my-bucket/*",
      "Condition": {
        "IpAddress": {
          "aws:SourceIp": "203.0.113.0/24"
        }
      }
    }
  ]
}

What this policy means:

  • Version: Using the current policy language version
  • Effect: Allow (grant permission)
  • Action: Can perform GetObject (download) and PutObject (upload) on S3
  • Resource: Only on objects in "my-bucket" (/* means all objects)
  • Condition: Only when request comes from IP range 203.0.113.0/24

Must Know (Critical Facts):

  • Explicit Deny always wins - if any policy denies, access is denied regardless of allows
  • Default is Deny - if no policy explicitly allows, access is denied
  • Policies are evaluated together - all applicable policies are combined
  • Resource ARNs follow pattern: arn:aws:service:region:account:resource
  • Wildcards (*) match multiple values - s3:* matches all S3 actions

💡 Tip: When reading policies, start with Effect (Allow/Deny), then Action (what), then Resource (where), then Condition (when).

Terminology Guide

Term Definition Example
Principal An entity that can make requests to AWS (user, role, service) IAM user "john", IAM role "lambda-execution-role"
Authentication Proving who you are Logging in with username and password
Authorization Determining what you're allowed to do IAM policy allowing S3 access
Encryption at Rest Encrypting data stored on disk Encrypting an EBS volume with KMS
Encryption in Transit Encrypting data moving over a network Using HTTPS instead of HTTP
Least Privilege Granting only the minimum permissions needed Allowing only s3:GetObject, not s3:*
Defense in Depth Multiple layers of security controls Security groups + NACLs + WAF
Bastion Host A server used to access private resources EC2 instance in public subnet for SSH access
NAT Gateway Allows private subnet resources to reach internet Enables private EC2 to download updates
VPC Endpoint Private connection to AWS services without internet Access S3 without going through internet gateway
Security Group Virtual firewall for EC2 instances (stateful) Allow port 443 from anywhere
NACL Network Access Control List (stateless firewall) Deny all traffic from specific IP range
IAM Role Set of permissions that can be assumed EC2 instance role for S3 access
IAM Policy Document defining permissions JSON document allowing S3 read access
KMS Key Management Service for encryption keys Service for creating and managing encryption keys
CloudTrail Service that logs all API calls Records who did what and when
CloudWatch Monitoring and logging service Collects metrics and logs from resources
GuardDuty Threat detection service Identifies suspicious activity
Security Hub Centralized security findings Aggregates findings from multiple services

Mental Model: How AWS Security Fits Together

Understanding how all AWS security services and concepts relate to each other is crucial. Here's the big picture:

📊 AWS Security Ecosystem Diagram:

graph TB
    subgraph "Identity & Access"
        A[IAM Users/Roles]
        B[IAM Policies]
        C[MFA]
    end
    
    subgraph "Network Security"
        D[VPC]
        E[Security Groups]
        F[NACLs]
        G[WAF]
    end
    
    subgraph "Data Protection"
        H[KMS Encryption]
        I[S3 Encryption]
        J[EBS Encryption]
    end
    
    subgraph "Monitoring & Detection"
        K[CloudTrail]
        L[CloudWatch]
        M[GuardDuty]
        N[Security Hub]
    end
    
    subgraph "Incident Response"
        O[Lambda Automation]
        P[Systems Manager]
        Q[Detective]
    end
    
    A --> B
    B --> C
    
    D --> E
    E --> F
    F --> G
    
    H --> I
    H --> J
    
    K --> L
    L --> M
    M --> N
    
    N --> O
    O --> P
    P --> Q
    
    B -.Controls Access.-> D
    B -.Controls Access.-> H
    K -.Logs Activity.-> A
    M -.Detects Threats.-> D
    N -.Aggregates.-> M
    
    style A fill:#ffcdd2
    style D fill:#c8e6c9
    style H fill:#fff9c4
    style K fill:#bbdefb
    style O fill:#f3e5f5

See: diagrams/01_fundamentals_security_ecosystem.mmd

Diagram Explanation (Detailed):

The AWS Security Ecosystem diagram shows how different security services and concepts work together to protect your AWS environment. At the top left (red), Identity & Access components (IAM users, roles, policies, MFA) control WHO can access resources. These policies control access to both network resources (VPC) and data protection services (KMS), shown by the dotted lines. In the top right (green), Network Security components (VPC, security groups, NACLs, WAF) control HOW resources communicate and what traffic is allowed. Below that (yellow), Data Protection services (KMS, S3 encryption, EBS encryption) ensure data is encrypted at rest. In the bottom left (blue), Monitoring & Detection services (CloudTrail, CloudWatch, GuardDuty, Security Hub) continuously watch for security events and threats. CloudTrail logs all IAM activity, GuardDuty detects threats in network traffic, and Security Hub aggregates findings from multiple sources. Finally, on the bottom right (purple), Incident Response tools (Lambda, Systems Manager, Detective) automate responses to security events and help investigate incidents. The flow shows how identity controls access, monitoring detects issues, and incident response tools remediate problems. Every security decision you make in AWS involves multiple layers from this ecosystem working together.

How to think about AWS security:

  1. Start with Identity (IAM): Who is accessing? What are they allowed to do?
  2. Add Network Controls (VPC, Security Groups): How are they accessing? From where?
  3. Protect Data (Encryption): Is sensitive data encrypted at rest and in transit?
  4. Monitor Everything (CloudTrail, CloudWatch): What's happening? Are there anomalies?
  5. Detect Threats (GuardDuty, Security Hub): Are there security issues?
  6. Respond to Incidents (Lambda, Systems Manager): How do we fix problems quickly?

This layered approach is called "Defense in Depth" - multiple security controls working together so that if one fails, others still protect your resources.

📝 Practice Exercise:

Imagine you're securing a web application with a database:

  1. Identity: Create IAM roles for EC2 instances (not users with long-term credentials)
  2. Network: Place web servers in public subnet, database in private subnet
  3. Access Control: Security group on web servers allows 443 from internet, security group on database allows 3306 only from web servers
  4. Encryption: Enable EBS encryption on all volumes, enable RDS encryption, use HTTPS for web traffic
  5. Monitoring: Enable CloudTrail for API logging, CloudWatch for metrics, GuardDuty for threat detection
  6. Response: Create Lambda function to automatically isolate compromised instances

This is defense in depth - multiple layers protecting your application.

Check Your Understanding

Before moving to the next chapter, ensure you can answer these questions:

  • Can you explain the AWS Shared Responsibility Model and give examples of AWS vs. customer responsibilities?
  • Can you describe the three principles of the CIA Triad and give an AWS service example for each?
  • Can you explain the difference between Regions, Availability Zones, and Edge Locations?
  • Can you read a CIDR block (e.g., 10.0.0.0/16) and determine how many IP addresses it contains?
  • Can you explain the difference between TCP and UDP?
  • Can you read a basic IAM policy and explain what it allows or denies?
  • Can you explain what "stateful" means in the context of security groups?
  • Can you describe what a private subnet is and why you'd use one?

If you answered "no" to any of these, review the relevant section before proceeding. These concepts are foundational to everything else in this guide.

Chapter Summary

What We Covered

AWS Shared Responsibility Model: AWS secures the infrastructure (OF the cloud), you secure your configurations and data (IN the cloud)

CIA Triad: Confidentiality (encryption, access control), Integrity (versioning, immutability), Availability (Multi-AZ, backups)

AWS Global Infrastructure: Regions (geographic areas), Availability Zones (isolated data centers), Edge Locations (CDN endpoints)

Networking Basics: IP addresses, CIDR notation, ports, protocols, subnets, routing

JSON and Policies: Structure of IAM policies, how to read and understand permission documents

Security Ecosystem: How IAM, network controls, encryption, monitoring, and incident response work together

Critical Takeaways

  1. Shared Responsibility: You are ALWAYS responsible for data, access control, and encryption configuration
  2. Defense in Depth: Use multiple layers of security controls, not just one
  3. Multi-AZ for Availability: Deploy across multiple AZs to survive data center failures
  4. Private Subnets for Security: Keep databases and internal services in private subnets
  5. Least Privilege: Grant only the minimum permissions needed
  6. Monitor Everything: Enable CloudTrail, CloudWatch, and GuardDuty from day one

Next Steps

Now that you understand the fundamentals, you're ready to dive into specific AWS security domains. The next chapter covers Threat Detection and Incident Response, where you'll learn about GuardDuty, Security Hub, Detective, and how to respond to security incidents.

Proceed to: 02_domain1_threat_detection


Chapter 0 Complete


Section 4: AWS Security Best Practices and Exam Preparation

Introduction

The problem: Understanding individual security services is not enough for the exam. You must understand AWS security best practices, the Well-Architected Framework security pillar, and how to apply security principles in real-world scenarios.

The solution: AWS provides comprehensive security best practices through the Well-Architected Framework, security whitepapers, and service-specific guidance. Understanding these best practices is essential for exam success.

Why it's tested: The exam tests your ability to apply security best practices, not just memorize service features. You must demonstrate understanding of WHY certain approaches are recommended and WHEN to use them.

AWS Well-Architected Framework - Security Pillar

What it is: The AWS Well-Architected Framework provides best practices for building secure, high-performing, resilient, and efficient infrastructure. The Security Pillar focuses on protecting information, systems, and assets.

The Five Design Principles:

  1. Implement a strong identity foundation

    • Use centralized identity management (IAM Identity Center, federation)
    • Implement least privilege access
    • Eliminate long-term credentials (use temporary credentials from STS)
    • Enforce MFA for privileged access
    • Audit and rotate credentials regularly
  2. Enable traceability

    • Log and monitor all actions (CloudTrail, VPC Flow Logs, application logs)
    • Integrate logs with SIEM or security analytics tools
    • Automate responses to security events (EventBridge, Lambda)
    • Implement alerting for suspicious activity (CloudWatch, Security Hub)
  3. Apply security at all layers

    • Defense-in-depth: multiple layers of security controls
    • Edge security (WAF, Shield, CloudFront)
    • Network security (security groups, NACLs, Network Firewall)
    • Compute security (hardened AMIs, vulnerability scanning)
    • Application security (input validation, secure coding)
    • Data security (encryption at rest and in transit)
  4. Automate security best practices

    • Use infrastructure as code (CloudFormation, CDK)
    • Implement automated security testing (Inspector, Security Hub)
    • Automate remediation (EventBridge, Lambda, Systems Manager)
    • Use managed services to reduce operational burden
    • Implement continuous compliance monitoring (Config, Audit Manager)
  5. Protect data in transit and at rest

    • Encrypt data at rest (KMS, S3 encryption, EBS encryption)
    • Encrypt data in transit (TLS, VPN, MACsec)
    • Implement access controls (IAM, resource policies, bucket policies)
    • Classify data and apply appropriate protections (Macie)
    • Implement data lifecycle management (S3 Lifecycle, Backup)

Exam Application: When you see a scenario question, evaluate the options against these five principles. The correct answer typically aligns with multiple principles.

Common Security Anti-Patterns (What NOT to Do)

Anti-Pattern 1: Using Root Account for Daily Operations

  • Wrong: Using root account credentials for application access
  • Correct: Create IAM users/roles, enable MFA on root, lock root credentials in safe
  • Why: Root account has unrestricted access; compromise = complete account takeover

Anti-Pattern 2: Embedding Credentials in Code

  • Wrong: Hardcoding AWS access keys in application code
  • Correct: Use IAM roles for EC2/Lambda, Secrets Manager for database credentials
  • Why: Credentials in code can be exposed in version control, logs, or memory dumps

Anti-Pattern 3: Overly Permissive Security Groups

  • Wrong: Security group allowing 0.0.0.0/0 on all ports
  • Correct: Security group allowing only required ports from specific sources
  • Why: Overly permissive rules expose resources to unnecessary risk

Anti-Pattern 4: No Logging or Monitoring

  • Wrong: Deploying resources without CloudTrail, VPC Flow Logs, or CloudWatch
  • Correct: Enable comprehensive logging and monitoring from day one
  • Why: Without logs, you cannot detect threats, investigate incidents, or prove compliance

Anti-Pattern 5: Unencrypted Data

  • Wrong: Storing sensitive data in S3 without encryption
  • Correct: Enable default encryption, use KMS customer-managed keys for sensitive data
  • Why: Unencrypted data can be exposed if access controls are misconfigured

Anti-Pattern 6: No Backup Strategy

  • Wrong: Relying on single-region, single-copy data storage
  • Correct: Implement automated backups, cross-region replication, immutable backups
  • Why: Data loss from deletion, corruption, or regional failure can be catastrophic

Anti-Pattern 7: Ignoring Least Privilege

  • Wrong: Granting : permissions to simplify access management
  • Correct: Grant only required permissions, use IAM Access Analyzer to identify unused permissions
  • Why: Excessive permissions increase blast radius of compromised credentials

Anti-Pattern 8: No Incident Response Plan

  • Wrong: Waiting until an incident occurs to figure out response procedures
  • Correct: Create incident response playbooks, automate responses, practice with simulations
  • Why: Delayed response increases damage from security incidents

Security Exam Strategies

Strategy 1: Identify the Security Requirement

  • Read the scenario carefully to identify: confidentiality, integrity, availability, compliance
  • Determine which security domains are involved: identity, network, data, logging, governance
  • Eliminate options that don't address the core requirement

Strategy 2: Look for Defense-in-Depth

  • Correct answers often involve multiple layers of security
  • Single-service solutions are usually incomplete
  • Example: "WAF + Shield + Security Groups + Network Firewall" is better than just "WAF"

Strategy 3: Prefer Managed Services

  • AWS managed services reduce operational burden and security risks
  • Example: Use Secrets Manager instead of storing credentials in Parameter Store
  • Managed services often have built-in security features

Strategy 4: Automate Everything

  • Automation reduces human error and improves response time
  • Look for EventBridge, Lambda, Step Functions in correct answers
  • Manual processes are rarely the best answer

Strategy 5: Encryption is Almost Always Correct

  • When in doubt, choose the option with encryption
  • KMS customer-managed keys provide more control than AWS-managed keys
  • Encryption at rest AND in transit is better than just one

Strategy 6: Least Privilege is Non-Negotiable

  • Never choose options with overly broad permissions
  • IAM policies should grant minimum required permissions
  • Use conditions to further restrict access

Strategy 7: Logging and Monitoring are Essential

  • Correct solutions include logging (CloudTrail, VPC Flow Logs)
  • Monitoring and alerting (CloudWatch, Security Hub) are critical
  • Without visibility, you cannot detect or respond to threats

Strategy 8: Consider Cost and Operational Overhead

  • When multiple options are secure, choose the most cost-effective
  • Consider operational complexity - simpler is often better
  • Managed services reduce operational overhead

Key Exam Topics Summary

Identity and Access Management:

  • IAM policies (identity-based, resource-based, permissions boundaries, SCPs)
  • Federation (SAML, OIDC, Cognito)
  • Temporary credentials (STS, AssumeRole)
  • MFA enforcement
  • ABAC vs RBAC

Network Security:

  • VPC security (security groups, NACLs, Network Firewall)
  • Edge security (WAF, Shield, CloudFront)
  • Private connectivity (VPC endpoints, PrivateLink, Transit Gateway)
  • VPN and Direct Connect security

Data Protection:

  • Encryption at rest (KMS, S3, EBS, RDS)
  • Encryption in transit (TLS, VPN, MACsec)
  • Key management (KMS, CloudHSM)
  • Secrets management (Secrets Manager, Parameter Store)
  • Data lifecycle (S3 Lifecycle, Backup, Object Lock)

Logging and Monitoring:

  • CloudTrail (management events, data events, Insights)
  • VPC Flow Logs
  • CloudWatch (Logs, Metrics, Alarms, Logs Insights)
  • Log analysis (Athena, CloudWatch Logs Insights)

Threat Detection and Response:

  • GuardDuty (threat detection)
  • Security Hub (aggregated findings)
  • Macie (sensitive data discovery)
  • Inspector (vulnerability scanning)
  • Detective (investigation)
  • Automated response (EventBridge, Lambda, Step Functions)

Governance and Compliance:

  • Organizations and SCPs
  • Control Tower (landing zones, guardrails)
  • Config (compliance monitoring, remediation)
  • Audit Manager (evidence collection)
  • CloudFormation (infrastructure as code)
  • Service Catalog (approved services)

Final Preparation Tips

1. Hands-On Practice:

  • Create a free-tier AWS account and practice
  • Deploy security services (GuardDuty, Security Hub, Config)
  • Create IAM policies and test with Policy Simulator
  • Analyze CloudTrail logs with Athena
  • Build automated response workflows with EventBridge and Lambda

2. Review AWS Documentation:

  • Read security best practices whitepapers
  • Review service FAQs for security-related questions
  • Study AWS Security Blog for real-world examples
  • Review Well-Architected Framework Security Pillar

3. Practice Questions:

  • Complete all practice test bundles in this package
  • Review explanations for both correct and incorrect answers
  • Identify patterns in question types
  • Time yourself to practice exam pacing

4. Understand WHY, Not Just WHAT:

  • Don't just memorize service features
  • Understand WHY certain approaches are recommended
  • Know WHEN to use each service
  • Understand trade-offs between options

5. Focus on Integration:

  • Understand how services work together
  • Practice designing end-to-end solutions
  • Think about defense-in-depth
  • Consider all aspects: detection, response, logging, compliance

6. Common Exam Scenarios:

  • Compromised credentials → Automated response
  • Data breach → Encryption, access controls, monitoring
  • Compliance audit → Config, Audit Manager, CloudTrail
  • Multi-account governance → Organizations, Control Tower, SCPs
  • Network security → Defense-in-depth with multiple layers
  • Incident investigation → CloudTrail, VPC Flow Logs, Detective

7. Time Management:

  • 170 minutes for 65 questions = ~2.6 minutes per question
  • Flag difficult questions and return later
  • Don't spend more than 3 minutes on any single question initially
  • Review flagged questions if time permits

8. Exam Day Strategy:

  • Read questions carefully - identify key requirements
  • Eliminate obviously wrong answers first
  • Look for keywords: "most secure", "least operational overhead", "most cost-effective"
  • Choose answers that align with AWS best practices
  • Trust your preparation - don't second-guess

You're Ready When...

  • You score 75%+ on all practice tests consistently
  • You can explain WHY answers are correct, not just WHAT they are
  • You recognize common question patterns instantly
  • You can design end-to-end security solutions
  • You understand service integrations and dependencies
  • You can troubleshoot security issues systematically
  • You know when to use each security service
  • You understand trade-offs between different approaches

Remember: The exam tests practical security knowledge, not just memorization. Focus on understanding concepts, applying best practices, and designing real-world solutions.

Good luck on your AWS Certified Security - Specialty exam!


Chapter 1: Threat Detection and Incident Response (14% of exam)

Chapter Overview

What you'll learn:

  • How to design and implement incident response plans
  • How to detect security threats and anomalies using AWS services
  • How to respond to compromised resources and workloads
  • How to use GuardDuty, Security Hub, Detective, Macie, Inspector, and Config
  • How to automate incident response with Lambda, Step Functions, and EventBridge

Time to complete: 8-10 hours
Prerequisites: Chapter 0 (Fundamentals)
Exam weight: 14% (approximately 7 questions on the exam)

Why this domain matters: Threat detection and incident response are critical security capabilities. You must be able to identify when something bad is happening in your AWS environment and respond quickly to minimize damage. This domain tests your ability to use AWS security services to detect threats, investigate incidents, and automate responses.


Section 1: Threat Detection Services Overview

Introduction

The problem: Traditional security approaches rely on perimeter defenses (firewalls, network controls). But in the cloud, the perimeter is fluid - resources are created and destroyed dynamically, users access from anywhere, and attackers use sophisticated techniques to evade detection. You need continuous monitoring and intelligent threat detection.

The solution: AWS provides multiple threat detection services that continuously analyze logs, network traffic, and resource configurations to identify suspicious activity. These services use machine learning, threat intelligence, and behavioral analysis to detect threats that traditional tools miss.

Why it's tested: The exam heavily tests your understanding of which threat detection service to use for different scenarios, how to configure them, and how to respond to their findings.

Core Threat Detection Services

Amazon GuardDuty - Intelligent Threat Detection

What it is: Amazon GuardDuty is a managed threat detection service that continuously monitors your AWS accounts and workloads for malicious activity and unauthorized behavior.

Why it exists: Manually analyzing CloudTrail logs, VPC Flow Logs, and DNS logs to find threats is time-consuming and error-prone. GuardDuty automates this analysis using machine learning, anomaly detection, and integrated threat intelligence to identify threats you might miss.

Real-world analogy: Think of GuardDuty as a security guard with AI-powered surveillance cameras. Instead of you watching hours of footage looking for suspicious activity, the AI automatically identifies unusual behavior (someone trying doors at 3 AM, unfamiliar faces, suspicious packages) and alerts you immediately.

How it works (Detailed step-by-step):

  1. Automatic Data Source Ingestion:

    • When you enable GuardDuty, it automatically starts analyzing foundational data sources
    • CloudTrail management events: API calls made in your account (who did what, when)
    • VPC Flow Logs: Network traffic metadata (source/destination IPs, ports, protocols)
    • DNS logs: DNS queries made by resources in your VPCs
    • You don't need to enable these logs separately - GuardDuty accesses them directly
    • No impact on your existing CloudTrail or VPC Flow Logs configurations
  2. Optional Protection Plans (Enhanced Detection):

    • S3 Protection: Monitors S3 data events to detect suspicious access patterns
    • EKS Protection: Analyzes EKS audit logs and runtime activity
    • RDS Protection: Monitors RDS login activity for anomalous database access
    • Malware Protection: Scans EBS volumes and EC2 instances for malware
    • Lambda Protection: Monitors Lambda network activity for threats
    • Runtime Monitoring: Monitors OS-level and network activity on EC2, EKS, ECS
  3. Threat Intelligence and Machine Learning:

    • GuardDuty uses threat intelligence feeds from AWS and third-party sources
    • Maintains lists of known malicious IP addresses, domains, and file hashes
    • Machine learning models establish baselines of normal behavior for your environment
    • Detects anomalies that deviate from established baselines
    • Continuously updates models as your environment changes
  4. Finding Generation:

    • When GuardDuty detects a threat, it generates a "finding"
    • Each finding includes: severity (Low, Medium, High), finding type, affected resource, details
    • Findings are available in GuardDuty console, Security Hub, and via EventBridge
    • Findings include recommended remediation actions
  5. Extended Threat Detection (Multi-Stage Attacks):

    • Automatically enabled at no extra cost
    • Correlates events across data sources and time to identify attack sequences
    • Individual events might not be suspicious, but the sequence indicates an attack
    • Example: Credential compromise → privilege escalation → data exfiltration

📊 GuardDuty Architecture Diagram:

graph TB
    subgraph "Data Sources"
        A[CloudTrail Events]
        B[VPC Flow Logs]
        C[DNS Logs]
        D[S3 Data Events]
        E[EKS Audit Logs]
        F[RDS Login Activity]
    end
    
    subgraph "GuardDuty Service"
        G[Threat Intelligence Feeds]
        H[Machine Learning Models]
        I[Anomaly Detection Engine]
        J[Finding Generation]
    end
    
    subgraph "Outputs"
        K[GuardDuty Console]
        L[Security Hub]
        M[EventBridge]
        N[SNS Notifications]
    end
    
    A --> I
    B --> I
    C --> I
    D --> I
    E --> I
    F --> I
    
    G --> I
    H --> I
    
    I --> J
    J --> K
    J --> L
    J --> M
    M --> N
    
    style A fill:#e1f5fe
    style B fill:#e1f5fe
    style C fill:#e1f5fe
    style D fill:#e1f5fe
    style E fill:#e1f5fe
    style F fill:#e1f5fe
    style I fill:#fff9c4
    style J fill:#ffcdd2
    style K fill:#c8e6c9
    style L fill:#c8e6c9
    style M fill:#c8e6c9
    style N fill:#c8e6c9

See: diagrams/02_domain1_guardduty_architecture.mmd

Diagram Explanation (Detailed):

The GuardDuty Architecture diagram shows how GuardDuty continuously monitors multiple data sources to detect threats. At the top (blue), six data sources feed into GuardDuty: CloudTrail Events (API calls), VPC Flow Logs (network traffic), DNS Logs (DNS queries), S3 Data Events (S3 access patterns), EKS Audit Logs (Kubernetes activity), and RDS Login Activity (database access). These data sources are automatically ingested by GuardDuty - you don't need to configure log delivery. In the middle (yellow), the GuardDuty Service processes these data sources using Threat Intelligence Feeds (known malicious IPs, domains, file hashes), Machine Learning Models (behavioral baselines), and an Anomaly Detection Engine that correlates events to identify threats. When a threat is detected, the Finding Generation component (red) creates a detailed finding with severity, type, affected resource, and remediation recommendations. At the bottom (green), findings are delivered to multiple outputs: the GuardDuty Console for manual review, Security Hub for centralized security management, EventBridge for automated responses, and SNS for notifications to security teams. This architecture enables continuous, automated threat detection without requiring you to manually analyze logs or configure complex correlation rules.

Must Know (Critical Facts):

  • GuardDuty is a regional service - must be enabled in each region where you have resources
  • Foundational data sources are free - CloudTrail, VPC Flow Logs, DNS logs don't incur additional charges
  • Protection plans have additional costs - S3, EKS, RDS, Malware, Lambda, Runtime Monitoring are optional and priced separately
  • Findings have severity levels: Low (informational), Medium (suspicious), High (critical threat)
  • GuardDuty doesn't prevent threats - it detects and alerts; you must implement remediation
  • 30-day free trial - test GuardDuty in your environment before committing
  • Multi-account support - designate a GuardDuty administrator account to manage findings across accounts

Detailed Example 1: Detecting Compromised EC2 Instance (Cryptocurrency Mining)

Scenario: An attacker compromises an EC2 instance and installs cryptocurrency mining software.

What GuardDuty detects:

  1. VPC Flow Logs analysis: Instance communicating with known cryptocurrency mining pool IPs
  2. DNS Logs analysis: DNS queries to cryptocurrency mining domains
  3. CloudTrail analysis: Unusual API calls from the instance's IAM role
  4. Behavioral analysis: Significant increase in network traffic volume

Finding generated: "CryptoCurrency:EC2/BitcoinTool.B!DNS"

  • Severity: High
  • Description: EC2 instance is querying a domain associated with Bitcoin mining
  • Affected resource: Instance ID, VPC ID, subnet ID
  • Recommended action: Investigate the instance, isolate it, terminate if confirmed malicious

How you respond:

  1. Review the finding details in GuardDuty console
  2. Check CloudTrail logs for how the instance was compromised
  3. Isolate the instance by changing its security group to deny all traffic
  4. Create a snapshot of the EBS volume for forensic analysis
  5. Terminate the instance and launch a clean replacement
  6. Review IAM permissions to prevent similar compromises

Why this works: GuardDuty correlates multiple signals (DNS queries, network traffic, API calls) to identify the threat. A single signal might be missed, but the combination triggers a high-confidence finding.

Detailed Example 2: Detecting Credential Compromise (Unusual API Calls)

Scenario: An attacker steals AWS access keys and uses them from a different geographic location.

What GuardDuty detects:

  1. CloudTrail analysis: API calls from IP address in unusual geographic location
  2. Behavioral analysis: API calls at unusual time (3 AM when user normally works 9-5)
  3. Threat intelligence: API calls from IP address with poor reputation
  4. Pattern analysis: Rapid succession of API calls (automated tool behavior)

Finding generated: "UnauthorizedAccess:IAMUser/InstanceCredentialExfiltration"

  • Severity: High
  • Description: Credentials that were created exclusively for an EC2 instance are being used from an external IP
  • Affected resource: IAM user or role, source IP address
  • Recommended action: Rotate credentials immediately, review CloudTrail for unauthorized actions

How you respond:

  1. Immediately disable the compromised access keys
  2. Review CloudTrail to identify all actions taken with compromised credentials
  3. Assess damage: What resources were accessed? What data was exposed?
  4. Rotate all credentials for the affected user/role
  5. Enable MFA if not already enabled
  6. Implement IP-based conditions in IAM policies to restrict access

Why this works: GuardDuty's machine learning establishes normal behavior patterns for each IAM principal. When credentials are used in ways that deviate from the baseline (different location, different time, different API patterns), GuardDuty flags it as suspicious.

Detailed Example 3: Detecting Data Exfiltration (S3 Protection)

Scenario: An insider or attacker downloads large amounts of data from S3 buckets.

What GuardDuty detects (with S3 Protection enabled):

  1. S3 data events analysis: Unusual volume of GetObject API calls
  2. Behavioral analysis: Access pattern deviates from normal (downloading entire buckets)
  3. Threat intelligence: Requests from suspicious IP addresses or anonymous proxies
  4. Timing analysis: Bulk downloads occurring at unusual times

Finding generated: "Exfiltration:S3/ObjectRead.Unusual"

  • Severity: Medium to High
  • Description: An IAM entity invoked an S3 API in a suspicious way
  • Affected resource: S3 bucket name, IAM principal, source IP
  • Recommended action: Review S3 access logs, verify legitimacy, restrict access if unauthorized

How you respond:

  1. Review S3 access logs to identify exactly what was downloaded
  2. Check if the IAM principal should have access to this data
  3. Verify the source IP address is legitimate
  4. If unauthorized: Revoke IAM permissions, enable MFA Delete, enable S3 Object Lock
  5. If data is sensitive: Notify affected parties, assess compliance implications
  6. Implement S3 Access Points with VPC restrictions to limit access

Why this works: S3 Protection monitors S3 data events (which aren't included in foundational GuardDuty) to detect unusual access patterns. This is critical because S3 often contains sensitive data that attackers target for exfiltration.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "GuardDuty will automatically block threats"

    • Why it's wrong: GuardDuty is a detection service, not a prevention service
    • Correct understanding: GuardDuty generates findings; you must implement automated or manual remediation
  • Mistake 2: "I need to configure CloudTrail and VPC Flow Logs for GuardDuty"

    • Why it's wrong: GuardDuty accesses these data sources directly without requiring you to enable them
    • Correct understanding: GuardDuty automatically ingests foundational data sources; you don't need to configure anything
  • Mistake 3: "GuardDuty findings are always accurate"

    • Why it's wrong: GuardDuty can generate false positives, especially for unusual but legitimate activity
    • Correct understanding: Always investigate findings to confirm they're genuine threats before taking action

🔗 Connections to Other Topics:

  • Relates to Security Hub because: GuardDuty findings are aggregated in Security Hub for centralized management
  • Builds on EventBridge by: GuardDuty findings trigger EventBridge rules for automated remediation
  • Often used with Detective to: Investigate GuardDuty findings and perform root cause analysis

When to use (Comprehensive):

  • Use GuardDuty when: You need continuous, automated threat detection across your AWS environment
  • Enable S3 Protection when: You store sensitive data in S3 and need to detect unusual access patterns
  • Enable EKS Protection when: You run Kubernetes workloads and need to detect container threats
  • Enable Malware Protection when: You need to scan EC2 instances and EBS volumes for malware
  • Don't rely solely on GuardDuty when: You need real-time blocking (use WAF, Network Firewall for prevention)
  • Don't enable all protection plans when: Cost is a concern and you don't use those services (enable only what you need)

Limitations & Constraints:

  • Regional service: Must be enabled in each region separately
  • Findings delay: Typically 5-15 minutes from event to finding (not real-time)
  • No historical analysis: GuardDuty only analyzes data from when it's enabled forward
  • Protection plan costs: S3, EKS, RDS, Malware, Lambda, Runtime Monitoring have additional per-GB or per-instance charges
  • Finding retention: Findings are retained for 90 days in GuardDuty console
  • No custom rules: You can't create custom threat detection rules (use Security Hub custom insights instead)

💡 Tips for Understanding:

  • Think of GuardDuty as your security analyst: It watches everything and alerts you to suspicious activity
  • Severity matters: High severity findings require immediate attention; Low severity might be informational
  • Enable in all regions: Attackers often target regions you're not actively using
  • Use trusted IP lists: Reduce false positives by whitelisting known good IPs (your office, VPN endpoints)

AWS Security Hub - Centralized Security Management

What it is: AWS Security Hub is a Cloud Security Posture Management (CSPM) service that provides a comprehensive view of your security state across AWS accounts, aggregating findings from multiple AWS security services and third-party products.

Why it exists: Managing security findings from GuardDuty, Inspector, Macie, Config, IAM Access Analyzer, and other services separately is overwhelming. Security Hub centralizes all findings in one place, correlates them, prioritizes them, and helps you track compliance with security standards.

Real-world analogy: Think of Security Hub as a security operations center (SOC) dashboard. Instead of having separate monitors for each security camera, alarm system, and access control system, you have one unified dashboard showing all security events, prioritized by severity, with the ability to drill down into details and take action.

How it works (Detailed step-by-step):

  1. Finding Aggregation:

    • Security Hub receives findings from integrated AWS services (GuardDuty, Inspector, Macie, Config, IAM Access Analyzer, Firewall Manager, etc.)
    • Findings are normalized into AWS Security Finding Format (ASFF) - a standardized JSON format
    • Third-party security products can also send findings to Security Hub via ASFF
    • All findings appear in a single Security Hub dashboard
    • Findings are automatically deduplicated to avoid noise
  2. Security Standards and Controls:

    • Security Hub runs automated security checks against your resources
    • AWS Foundational Security Best Practices (FSBP): AWS's recommended security controls
    • CIS AWS Foundations Benchmark: Industry-standard security configuration baseline
    • PCI DSS: Payment Card Industry Data Security Standard controls
    • NIST 800-53: National Institute of Standards and Technology framework
    • Each standard contains multiple security controls (e.g., "S3 buckets should have encryption enabled")
    • Security Hub continuously evaluates your resources against these controls
  3. Security Score Calculation:

    • Security Hub calculates a security score (0-100%) for each standard
    • Score is based on the percentage of passed controls vs. total controls
    • Scores are calculated per account and aggregated across your organization
    • Helps you track security posture improvements over time
    • Identifies which accounts or controls need attention
  4. Insights and Filtering:

    • Managed Insights: Pre-built queries for common security scenarios (e.g., "Resources with critical findings")
    • Custom Insights: Create your own queries to filter findings by severity, resource type, compliance status, etc.
    • Group findings by resource, finding type, or other attributes
    • Track trends over time (are findings increasing or decreasing?)
  5. Automated Responses:

    • Integrate with EventBridge to trigger automated remediation
    • Use automation rules to automatically update finding status or suppress false positives
    • Create custom actions to send findings to ticketing systems or SIEM tools
    • Implement automated remediation workflows using Lambda or Systems Manager
  6. Cross-Region and Cross-Account Aggregation:

    • Designate one region as the aggregation region
    • Security Hub aggregates findings from all linked regions into the aggregation region
    • Designate an administrator account to manage Security Hub across multiple member accounts
    • View findings from all accounts and regions in a single dashboard

📊 Security Hub Architecture Diagram:

graph TB
    subgraph "Finding Sources"
        A[GuardDuty]
        B[Inspector]
        C[Macie]
        D[Config]
        E[IAM Access Analyzer]
        F[Firewall Manager]
        G[Third-Party Products]
    end
    
    subgraph "Security Hub"
        H[Finding Aggregation]
        I[ASFF Normalization]
        J[Security Standards]
        K[Security Score]
        L[Insights]
        M[Automation Rules]
    end
    
    subgraph "Outputs"
        N[Security Hub Dashboard]
        O[EventBridge]
        P[Custom Actions]
        Q[SIEM Integration]
    end
    
    A --> H
    B --> H
    C --> H
    D --> H
    E --> H
    F --> H
    G --> H
    
    H --> I
    I --> J
    J --> K
    I --> L
    I --> M
    
    K --> N
    L --> N
    M --> O
    O --> P
    O --> Q
    
    style H fill:#fff9c4
    style I fill:#fff9c4
    style J fill:#ffcdd2
    style K fill:#ffcdd2
    style L fill:#c8e6c9
    style M fill:#c8e6c9
    style N fill:#bbdefb
    style O fill:#bbdefb

See: diagrams/02_domain1_securityhub_architecture.mmd

Diagram Explanation (Detailed):

The Security Hub Architecture diagram illustrates how Security Hub acts as a central aggregation point for security findings from multiple sources. At the top, seven finding sources feed into Security Hub: GuardDuty (threat detection), Inspector (vulnerability scanning), Macie (sensitive data discovery), Config (configuration compliance), IAM Access Analyzer (access analysis), Firewall Manager (firewall policy compliance), and Third-Party Products (external security tools). All these findings flow into the Finding Aggregation component (yellow), which collects findings from all sources. The ASFF Normalization component converts all findings into a standardized format, making it possible to correlate and compare findings from different sources. In the middle (red), Security Standards continuously evaluate your resources against compliance frameworks (FSBP, CIS, PCI DSS, NIST), and Security Score calculates your overall security posture percentage. On the right (green), Insights provide pre-built and custom queries to filter and analyze findings, while Automation Rules automatically update or suppress findings based on criteria you define. At the bottom (blue), outputs include the Security Hub Dashboard for visualization, EventBridge for triggering automated responses, Custom Actions for integration with ticketing systems, and SIEM Integration for sending findings to external security information and event management tools. This architecture enables you to manage security across hundreds of accounts and multiple AWS services from a single pane of glass.

Must Know (Critical Facts):

  • Security Hub is a regional service - must be enabled in each region, but supports cross-region aggregation
  • Requires other services to be enabled - GuardDuty, Inspector, etc. must be enabled separately to send findings
  • ASFF is the standard format - all findings are normalized to AWS Security Finding Format
  • Security standards are optional - you can enable/disable individual standards based on your compliance needs
  • Findings have workflow status: NEW, NOTIFIED, SUPPRESSED, RESOLVED
  • 30-day free trial - includes security checks and finding ingestion
  • Administrator/member model - one administrator account manages Security Hub for multiple member accounts

Detailed Example 1: Centralizing Findings from Multiple Services

Scenario: You have GuardDuty, Inspector, and Macie enabled across 50 AWS accounts in 3 regions.

Without Security Hub:

  • Check GuardDuty console in each region for each account (150 separate checks)
  • Check Inspector console in each region for each account (150 separate checks)
  • Check Macie console in each region for each account (150 separate checks)
  • No way to correlate findings across services
  • No unified view of security posture
  • Manual tracking of remediation status

With Security Hub:

  1. Enable Security Hub in one administrator account
  2. Invite 50 member accounts to Security Hub
  3. Enable cross-region aggregation (choose us-east-1 as aggregation region)
  4. All findings from GuardDuty, Inspector, and Macie automatically flow to Security Hub
  5. View all findings in a single Security Hub dashboard in us-east-1
  6. Filter findings by severity, account, region, service, or resource type
  7. Track remediation progress with workflow status updates
  8. Generate reports showing security posture across all accounts

Why this works: Security Hub eliminates the need to check multiple consoles across multiple accounts and regions. All findings are centralized, normalized, and prioritized in one place.

Detailed Example 2: Compliance Monitoring with Security Standards

Scenario: Your organization must comply with PCI DSS for payment card processing.

How Security Hub helps:

  1. Enable the PCI DSS standard in Security Hub
  2. Security Hub automatically evaluates your resources against 43 PCI DSS controls
  3. Controls check for: encryption enabled, logging configured, access controls in place, network segmentation, etc.
  4. Security Hub generates findings for each failed control
  5. Dashboard shows your PCI DSS compliance score (e.g., 78% compliant)
  6. Drill down to see which specific controls are failing
  7. View affected resources for each failed control
  8. Implement remediation and watch your compliance score improve

Example findings:

  • [PCI.S3.1]: S3 buckets should prohibit public read access - FAILED (5 buckets)
  • [PCI.CloudTrail.1]: CloudTrail should be enabled - PASSED
  • [PCI.IAM.1]: IAM root user access key should not exist - FAILED (1 account)
  • [PCI.EC2.2]: VPC default security group should not allow inbound and outbound traffic - FAILED (3 VPCs)

Remediation workflow:

  1. Click on failed finding to see affected resources
  2. Review remediation instructions provided by Security Hub
  3. Fix the issue (e.g., enable S3 Block Public Access)
  4. Security Hub re-evaluates the control (typically within 12-24 hours)
  5. Finding status changes from FAILED to PASSED
  6. Compliance score increases

Why this works: Security Hub automates compliance checking that would otherwise require manual audits. You get continuous compliance monitoring with clear remediation guidance.

Detailed Example 3: Automated Remediation with EventBridge

Scenario: You want to automatically remediate security group rules that allow unrestricted SSH access (0.0.0.0/0 on port 22).

Architecture:

  1. Security Hub runs the control check: [EC2.13] Security groups should not allow ingress from 0.0.0.0/0 to port 22
  2. When a security group violates this control, Security Hub generates a finding
  3. EventBridge rule matches findings with this specific control ID
  4. EventBridge triggers a Lambda function
  5. Lambda function:
    • Parses the finding to extract security group ID
    • Removes the offending rule (0.0.0.0/0:22)
    • Adds a restricted rule (your office IP range:22)
    • Updates the finding status to RESOLVED in Security Hub
    • Sends SNS notification to security team

EventBridge Rule Pattern:

{
  "source": ["aws.securityhub"],
  "detail-type": ["Security Hub Findings - Imported"],
  "detail": {
    "findings": {
      "ProductFields": {
        "ControlId": ["EC2.13"]
      },
      "Compliance": {
        "Status": ["FAILED"]
      }
    }
  }
}

Lambda Function Logic (pseudocode):

def lambda_handler(event, context):
    # Extract security group ID from finding
    sg_id = event['detail']['findings'][0]['Resources'][0]['Id']
    
    # Remove unrestricted SSH rule
    ec2.revoke_security_group_ingress(
        GroupId=sg_id,
        IpPermissions=[{
            'IpProtocol': 'tcp',
            'FromPort': 22,
            'ToPort': 22,
            'IpRanges': [{'CidrIp': '0.0.0.0/0'}]
        }]
    )
    
    # Add restricted SSH rule
    ec2.authorize_security_group_ingress(
        GroupId=sg_id,
        IpPermissions=[{
            'IpProtocol': 'tcp',
            'FromPort': 22,
            'ToPort': 22,
            'IpRanges': [{'CidrIp': '203.0.113.0/24', 'Description': 'Office IP'}]
        }]
    )
    
    # Update finding status
    securityhub.batch_update_findings(
        FindingIdentifiers=[...],
        Workflow={'Status': 'RESOLVED'}
    )
    
    # Send notification
    sns.publish(Topic=sns_topic, Message='Auto-remediated SSH security group')

Why this works: Automated remediation reduces the time between detection and remediation from hours/days to seconds. Security Hub findings trigger immediate corrective action without human intervention.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Security Hub detects threats like GuardDuty"

    • Why it's wrong: Security Hub aggregates findings from other services but doesn't perform threat detection itself
    • Correct understanding: Security Hub is a centralization and compliance tool; GuardDuty, Inspector, etc. do the actual detection
  • Mistake 2: "Enabling Security Hub automatically enables GuardDuty, Inspector, etc."

    • Why it's wrong: Security Hub only aggregates findings; you must enable source services separately
    • Correct understanding: Enable GuardDuty, Inspector, Macie, etc. first, then enable Security Hub to aggregate their findings
  • Mistake 3: "Security Hub findings are real-time"

    • Why it's wrong: Security standards checks run periodically (typically every 12-24 hours)
    • Correct understanding: Findings from GuardDuty/Inspector are near real-time, but compliance checks are periodic

🔗 Connections to Other Topics:

  • Relates to GuardDuty because: Security Hub aggregates GuardDuty findings for centralized management
  • Builds on EventBridge by: Security Hub findings trigger EventBridge rules for automated remediation
  • Often used with Config to: Config evaluates resource configurations, Security Hub aggregates Config findings

When to use (Comprehensive):

  • Use Security Hub when: You have multiple AWS accounts and need centralized security management
  • Enable security standards when: You need to demonstrate compliance with industry frameworks (CIS, PCI DSS, NIST)
  • Use cross-region aggregation when: You deploy resources in multiple regions and want a single view
  • Use automation rules when: You have recurring false positives that need automatic suppression
  • Don't use Security Hub alone when: You need actual threat detection (enable GuardDuty, Inspector, etc. first)
  • Don't enable all standards when: You only need specific compliance frameworks (enable only what you need)

Limitations & Constraints:

  • Regional service: Must be enabled in each region, though cross-region aggregation is supported
  • Finding retention: Findings are retained for 90 days
  • Standards checks frequency: Most checks run every 12-24 hours (not real-time)
  • Maximum accounts: Up to 5,000 member accounts per administrator account
  • Maximum findings: No hard limit, but performance may degrade with millions of findings
  • Custom controls: You cannot create custom security controls (use Config custom rules instead)

💡 Tips for Understanding:

  • Think of Security Hub as an aggregator, not a detector: It collects findings from other services
  • Start with FSBP standard: AWS Foundational Security Best Practices is a good starting point
  • Use insights to filter noise: Create custom insights to focus on high-priority findings
  • Automate remediation: Use EventBridge + Lambda to automatically fix common issues

Amazon Detective - Security Investigation and Analysis

What it is: Amazon Detective is a security investigation service that automatically collects log data from your AWS resources and uses machine learning, statistical analysis, and graph theory to help you analyze and investigate the root cause of security findings.

Why it exists: When GuardDuty or Security Hub generates a finding, you need to investigate: What happened? How did it happen? What's the scope of the incident? Manually analyzing CloudTrail logs, VPC Flow Logs, and other data sources is time-consuming and requires expertise. Detective automates this analysis and visualizes relationships between entities to help you understand security incidents quickly.

Real-world analogy: Think of Detective as a forensic investigator with a crime scene analysis lab. When a security alarm goes off (GuardDuty finding), Detective examines all the evidence (logs, network traffic, API calls), creates a timeline of events, identifies connections between suspects (IP addresses, users, resources), and presents you with a visual investigation report showing exactly what happened and how.

How it works (Detailed step-by-step):

  1. Automatic Data Collection and Behavior Graph:

    • Detective automatically ingests data from CloudTrail, VPC Flow Logs, EKS audit logs, and GuardDuty findings
    • Creates a "behavior graph" - a linked dataset of entities (users, roles, IP addresses, EC2 instances, S3 buckets) and their interactions
    • Stores up to 1 year of historical data for analysis
    • Continuously updates the graph as new data arrives
    • No configuration required - just enable Detective and it starts collecting
  2. Entity Profiling and Baselines:

    • Detective profiles each entity (IAM user, role, IP address, resource) to establish normal behavior
    • Tracks metrics like: API call volume, failed authentication attempts, data transfer volume, geographic locations
    • Establishes baselines over time (e.g., "User Alice typically makes 50 API calls per day from US-East")
    • Identifies deviations from baselines (e.g., "User Alice made 5,000 API calls today from Russia")
  3. Investigation Workflows:

    • Finding Investigation: Start from a GuardDuty or Security Hub finding
    • Entity Investigation: Investigate a specific IAM user, role, IP address, or resource
    • Finding Groups: Detective automatically groups related findings that may be part of the same incident
    • Impossible Travel: Detects when credentials are used from geographically distant locations in an impossible timeframe
  4. Visualization and Analysis:

    • Interactive visualizations show relationships between entities
    • Timeline views show sequence of events leading to a security incident
    • Scope views show all resources affected by an incident
    • Comparison views show current behavior vs. historical baselines
    • Drill-down capabilities to examine specific API calls, network connections, or resource access
  5. Investigation Reports:

    • Detective generates investigation reports summarizing findings
    • Reports include: timeline of events, affected resources, anomalous behaviors, recommended next steps
    • Export reports for documentation or sharing with stakeholders

📊 Detective Investigation Flow Diagram:

sequenceDiagram
    participant GD as GuardDuty
    participant DT as Detective
    participant CT as CloudTrail
    participant VPC as VPC Flow Logs
    participant Analyst as Security Analyst
    
    GD->>DT: Finding: Unusual API calls from IP 203.0.113.50
    DT->>CT: Query: All API calls from 203.0.113.50
    DT->>VPC: Query: All network connections to/from 203.0.113.50
    DT->>DT: Build behavior graph
    DT->>DT: Compare to baseline behavior
    DT->>DT: Identify related entities
    DT->>Analyst: Present investigation: Timeline, Scope, Anomalies
    Analyst->>DT: Drill down: What did this IP access?
    DT->>Analyst: Show: S3 buckets accessed, EC2 instances launched, IAM changes
    Analyst->>DT: Investigate: Related IAM user
    DT->>Analyst: Show: User's normal behavior vs. current behavior
    Analyst->>Analyst: Determine: Compromised credentials
    Analyst->>Analyst: Action: Rotate credentials, revoke sessions

See: diagrams/02_domain1_detective_investigation_flow.mmd

Diagram Explanation (Detailed):

The Detective Investigation Flow diagram shows the sequence of events during a security investigation using Amazon Detective. The process begins when GuardDuty detects unusual API calls from a suspicious IP address (203.0.113.50) and sends a finding to Detective. Detective immediately queries CloudTrail for all API calls made from that IP address and VPC Flow Logs for all network connections involving that IP. Detective then builds a behavior graph connecting the IP address to IAM users, roles, resources accessed, and other related entities. It compares the current activity to historical baselines to identify anomalies. The Security Analyst receives an investigation report showing a timeline of events, the scope of affected resources, and identified anomalies. The analyst can drill down to see exactly what the suspicious IP accessed - which S3 buckets were read, which EC2 instances were launched, what IAM changes were made. The analyst can then investigate related entities, such as the IAM user whose credentials were used. Detective shows the user's normal behavior pattern compared to the current suspicious behavior, helping the analyst determine that the credentials were compromised. Armed with this information, the analyst takes action: rotating credentials and revoking active sessions. This entire investigation, which could take hours or days manually analyzing logs, is completed in minutes with Detective's automated analysis and visualization.

Must Know (Critical Facts):

  • Detective requires GuardDuty - GuardDuty must be enabled for at least 48 hours before enabling Detective
  • Behavior graph takes time to build - needs 2 weeks of data for accurate baselines
  • 1 year of data retention - Detective stores up to 1 year of historical data for analysis
  • Regional service - must be enabled in each region where you want to investigate
  • Administrator/member model - one administrator account can manage Detective for multiple member accounts
  • Pricing based on data volume - charged per GB of data ingested into the behavior graph
  • No findings generated - Detective is for investigation, not detection (use GuardDuty for detection)

Detailed Example 1: Investigating Compromised IAM Credentials

Scenario: GuardDuty generates a finding: "UnauthorizedAccess:IAMUser/InstanceCredentialExfiltration" for IAM user "john.doe".

Investigation with Detective:

  1. Start Investigation:

    • Click on the GuardDuty finding in Security Hub
    • Click "Investigate in Detective" button
    • Detective opens with the IAM user "john.doe" as the focus entity
  2. Review Entity Profile:

    • Normal behavior: John typically makes 20-30 API calls per day, all from US office IP (203.0.113.0/24)
    • Current behavior: 500 API calls in the last hour from IP 198.51.100.50 (Russia)
    • Anomaly detected: 1,600% increase in API call volume, new geographic location
  3. Examine Timeline:

    • 10:00 AM: Normal API calls from office IP (DescribeInstances, ListBuckets)
    • 10:15 AM: First API call from Russian IP (GetUser - checking permissions)
    • 10:16 AM: Rapid succession of API calls from Russian IP (ListUsers, ListRoles, DescribeSecurityGroups)
    • 10:20 AM: Sensitive API calls (GetObject on S3 buckets, DescribeDBInstances)
    • 10:30 AM: GuardDuty generates finding
  4. Identify Scope:

    • Resources accessed: 15 S3 buckets (3 containing sensitive customer data), 5 RDS databases, 20 EC2 instances
    • Data exfiltrated: 2.5 GB downloaded from S3 buckets
    • Changes made: None (read-only access, no modifications)
  5. Determine Root Cause:

    • Detective shows: John's access keys were created 6 months ago and never rotated
    • CloudTrail shows: Access keys used from both office IP and Russian IP simultaneously (impossible for one person)
    • Conclusion: Access keys were compromised (leaked, phished, or stolen)
  6. Remediation Actions:

    • Immediately disable John's access keys
    • Rotate all credentials for John
    • Review CloudTrail for all actions taken with compromised keys
    • Assess data exposure (what sensitive data was accessed?)
    • Enable MFA for John's account
    • Implement IAM policy requiring MFA for sensitive operations
    • Set up CloudWatch alarm for unusual API call volumes

Why this works: Detective automatically correlates data from multiple sources (CloudTrail, VPC Flow Logs, GuardDuty) and visualizes the timeline and scope of the incident. What would take hours of manual log analysis is completed in minutes.

Detailed Example 2: Investigating Impossible Travel

Scenario: Detective's Impossible Travel detection flags that IAM user "alice" was used from New York at 9:00 AM and from Tokyo at 9:05 AM (impossible to travel that distance in 5 minutes).

Investigation with Detective:

  1. Review Impossible Travel Finding:

    • First location: New York (IP: 203.0.113.10) at 9:00 AM
    • Second location: Tokyo (IP: 198.51.100.20) at 9:05 AM
    • Distance: ~6,700 miles
    • Time difference: 5 minutes
    • Conclusion: Credentials are being used by multiple parties
  2. Analyze API Calls from Each Location:

    • New York IP (legitimate):
      • Normal API calls: DescribeInstances, ListBuckets, GetObject
      • Consistent with Alice's typical work patterns
      • Office IP address (known good)
    • Tokyo IP (suspicious):
      • Unusual API calls: CreateUser, AttachUserPolicy, CreateAccessKey
      • Attempting to create backdoor access
      • Unknown IP address (not in trusted IP list)
  3. Examine User Behavior:

    • Detective shows Alice's normal pattern: Works 9 AM - 5 PM EST, always from office IP
    • Current pattern: Simultaneous access from two locations
    • Anomaly: Tokyo IP is making IAM administrative calls (Alice is a developer, not an admin)
  4. Identify Attack Pattern:

    • 9:00 AM: Alice logs in from office (legitimate)
    • 9:05 AM: Attacker uses stolen credentials from Tokyo
    • 9:06 AM: Attacker attempts to create new IAM user (blocked by permissions)
    • 9:07 AM: Attacker attempts to escalate privileges (blocked by permissions)
    • 9:08 AM: Attacker downloads data from S3 (successful - Alice has read access)
  5. Determine Impact:

    • Privilege escalation: Attempted but failed (Alice doesn't have IAM admin permissions)
    • Data access: 500 MB downloaded from S3 (application logs, no sensitive data)
    • Persistence: No backdoor created (attempts were blocked)
  6. Remediation Actions:

    • Immediately terminate all active sessions for Alice
    • Rotate Alice's credentials
    • Review what data was accessed from Tokyo IP
    • Implement IP-based conditional access (restrict Alice's access to office IP range)
    • Enable MFA for Alice
    • Investigate how credentials were compromised (phishing? malware?)

Why this works: Detective's Impossible Travel detection automatically identifies credential sharing or compromise. The visualization shows exactly what each location accessed, making it easy to determine the scope and impact of the incident.

Detailed Example 3: Investigating Finding Groups (Multi-Stage Attack)

Scenario: Detective groups three related GuardDuty findings that appear to be part of a coordinated attack.

Finding Group:

  1. Finding 1: Reconnaissance - Port scanning from IP 198.51.100.30
  2. Finding 2: Initial Access - Brute force SSH attempts on EC2 instance i-1234567890abcdef0
  3. Finding 3: Exfiltration - Unusual data transfer from EC2 instance to external IP

Investigation with Detective:

  1. Review Finding Group:

    • Detective automatically groups these three findings because they involve the same EC2 instance and occur in sequence
    • Timeline shows clear attack progression: Recon → Access → Exfiltration
  2. Analyze Attack Timeline:

    • 2:00 PM: Port scanning detected (attacker probing for open ports)
    • 2:15 PM: SSH brute force attempts begin (attacker trying to gain access)
    • 2:45 PM: Successful SSH login (attacker gained access after 1,000+ attempts)
    • 3:00 PM: Large data transfer begins (attacker exfiltrating data)
    • 3:30 PM: GuardDuty generates findings
  3. Examine Network Connections:

    • Detective shows all network connections for the compromised EC2 instance
    • Inbound: SSH connections from attacker IP (198.51.100.30)
    • Outbound: Large data transfer to attacker-controlled server (198.51.100.40)
    • Volume: 10 GB transferred over 30 minutes
  4. Identify Compromised Resources:

    • Primary target: EC2 instance i-1234567890abcdef0 (web server)
    • Data accessed: Application database (MySQL running on same instance)
    • Data exfiltrated: Customer records (names, emails, addresses)
  5. Determine Attack Vector:

    • Detective shows: EC2 instance had security group allowing SSH from 0.0.0.0/0 (anywhere)
    • Weak SSH password (no key-based authentication)
    • No fail2ban or rate limiting on SSH
    • Attacker successfully brute-forced the password
  6. Remediation Actions:

    • Immediately isolate the compromised EC2 instance (change security group to deny all traffic)
    • Create EBS snapshot for forensic analysis
    • Terminate the compromised instance
    • Launch new instance with hardened configuration:
      • SSH only from bastion host (not from internet)
      • Key-based authentication only (no passwords)
      • fail2ban installed to block brute force attempts
    • Notify affected customers of data breach
    • Review all other EC2 instances for similar vulnerabilities

Why this works: Detective's Finding Groups feature automatically correlates related findings that are part of the same attack. This helps you understand the full scope of multi-stage attacks rather than treating each finding as an isolated incident.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Detective detects threats like GuardDuty"

    • Why it's wrong: Detective is for investigation and analysis, not threat detection
    • Correct understanding: GuardDuty detects threats, Detective helps you investigate them
  • Mistake 2: "Detective works immediately after enabling"

    • Why it's wrong: Detective needs 2 weeks of data to establish accurate behavioral baselines
    • Correct understanding: Enable Detective early so it has historical data when you need to investigate
  • Mistake 3: "Detective can investigate incidents from before it was enabled"

    • Why it's wrong: Detective only analyzes data from when it's enabled forward
    • Correct understanding: Enable Detective proactively, not reactively after an incident

🔗 Connections to Other Topics:

  • Relates to GuardDuty because: Detective investigates GuardDuty findings to determine root cause
  • Builds on CloudTrail by: Detective analyzes CloudTrail logs to build behavior graphs
  • Often used with Incident Response to: Quickly understand scope and impact of security incidents

Amazon Macie - Sensitive Data Discovery and Protection

What it is: Amazon Macie is a data security service that uses machine learning and pattern matching to discover, classify, and protect sensitive data in Amazon S3.

Why it exists: Organizations store massive amounts of data in S3, and it's difficult to know which buckets contain sensitive information like credit card numbers, social security numbers, API keys, or personally identifiable information (PII). Macie automatically scans your S3 buckets to identify sensitive data, assess security posture, and alert you to potential data exposure risks.

Real-world analogy: Think of Macie as a data auditor with a magnifying glass and a checklist. It goes through all your file cabinets (S3 buckets), examines every document (object), identifies which ones contain sensitive information (credit cards, SSNs, PII), checks if the cabinets are properly locked (bucket policies, encryption), and reports any issues (public buckets, unencrypted data, sensitive data in unexpected locations).

How it works (Detailed step-by-step):

  1. S3 Bucket Inventory and Assessment:

    • Macie automatically discovers all S3 buckets in your account
    • Evaluates bucket security and access controls
    • Identifies buckets that are publicly accessible
    • Checks if buckets have encryption enabled
    • Monitors for changes in bucket configurations
    • Generates findings for security issues (public buckets, unencrypted buckets, etc.)
  2. Automated Sensitive Data Discovery:

    • Macie continuously samples objects across all your S3 buckets
    • Uses statistical sampling to efficiently scan large datasets
    • Analyzes object metadata and content
    • Identifies which buckets likely contain sensitive data
    • Provides sensitivity scores for each bucket
    • Updates assessments as new data is added
  3. Sensitive Data Detection with Managed Data Identifiers:

    • Managed Data Identifiers: Pre-built patterns for common sensitive data types
      • Credit card numbers (Visa, Mastercard, Amex, Discover)
      • Social Security Numbers (SSNs)
      • Driver's license numbers
      • Passport numbers
      • Bank account numbers
      • AWS secret access keys
      • Private keys (RSA, SSH, PGP)
      • Email addresses, phone numbers, physical addresses
    • Macie scans objects and matches content against these patterns
    • Generates findings when sensitive data is detected
  4. Custom Data Identifiers:

    • Create custom patterns for organization-specific sensitive data
    • Use regular expressions to define patterns (e.g., employee IDs, customer account numbers)
    • Define keywords that indicate sensitive data (e.g., "confidential", "internal only")
    • Combine regex patterns with keywords for more accurate detection
    • Example: Detect internal employee IDs matching pattern "EMP-\d{6}"
  5. Sensitive Data Discovery Jobs:

    • One-time jobs: Scan specific buckets or objects on-demand
    • Scheduled jobs: Run scans daily, weekly, or monthly
    • Scope: Define which buckets, prefixes, or object types to scan
    • Sampling depth: Choose between sampling (faster, cheaper) or full scan (comprehensive)
    • Results: Detailed findings showing exactly where sensitive data was found
  6. Findings and Alerts:

    • Policy findings: Bucket security issues (public access, weak encryption, etc.)
    • Sensitive data findings: Objects containing sensitive data
    • Findings include: severity, bucket name, object key, data types found, sample occurrences
    • Integrate with Security Hub for centralized management
    • Trigger EventBridge rules for automated remediation

📊 Macie Sensitive Data Discovery Diagram:

graph TB
    subgraph "S3 Buckets"
        A[Bucket 1: Customer Data]
        B[Bucket 2: Application Logs]
        C[Bucket 3: Backups]
        D[Bucket 4: Public Website]
    end
    
    subgraph "Macie Service"
        E[Bucket Inventory]
        F[Security Assessment]
        G[Automated Discovery]
        H[Managed Data Identifiers]
        I[Custom Data Identifiers]
        J[Sensitive Data Jobs]
    end
    
    subgraph "Findings"
        K[Policy Findings]
        L[Sensitive Data Findings]
    end
    
    subgraph "Outputs"
        M[Macie Console]
        N[Security Hub]
        O[EventBridge]
    end
    
    A --> E
    B --> E
    C --> E
    D --> E
    
    E --> F
    E --> G
    
    G --> H
    G --> I
    G --> J
    
    F --> K
    H --> L
    I --> L
    J --> L
    
    K --> M
    L --> M
    K --> N
    L --> N
    K --> O
    L --> O
    
    style A fill:#ffcdd2
    style D fill:#ffcdd2
    style E fill:#fff9c4
    style F fill:#fff9c4
    style G fill:#fff9c4
    style K fill:#ff9800
    style L fill:#f44336
    style M fill:#c8e6c9
    style N fill:#c8e6c9
    style O fill:#c8e6c9

See: diagrams/02_domain1_macie_discovery.mmd

Diagram Explanation (Detailed):

The Macie Sensitive Data Discovery diagram illustrates how Macie protects sensitive data in S3. At the top, four S3 buckets represent different types of data storage: Customer Data (red - contains sensitive PII), Application Logs (may contain leaked credentials), Backups (may contain sensitive data), and Public Website (red - should not contain sensitive data but is publicly accessible). Macie's Bucket Inventory component (yellow) automatically discovers all S3 buckets in your account. The Security Assessment component evaluates each bucket's security posture - checking for public access, encryption status, and access controls. The Automated Discovery component continuously samples objects across buckets to identify which ones likely contain sensitive data. When scanning objects, Macie uses Managed Data Identifiers (pre-built patterns for credit cards, SSNs, etc.), Custom Data Identifiers (your organization-specific patterns), and Sensitive Data Jobs (scheduled or on-demand scans). Macie generates two types of findings: Policy Findings (orange) for security issues like public buckets or missing encryption, and Sensitive Data Findings (red) when sensitive data is detected in objects. These findings are delivered to the Macie Console for review, Security Hub for centralized management, and EventBridge for automated remediation. This architecture enables you to maintain visibility into where sensitive data resides and ensure it's properly protected.

Must Know (Critical Facts):

  • Macie is S3-specific - only scans S3 buckets, not other AWS services
  • Automated discovery uses sampling - doesn't scan every object (use jobs for comprehensive scans)
  • Managed data identifiers are free - no additional cost for using pre-built patterns
  • Custom data identifiers have limits - maximum 1,000 custom identifiers per account
  • Findings are retained for 90 days - export to S3 for longer retention
  • Regional service - must be enabled in each region where you have S3 buckets
  • Administrator/member model - one administrator account can manage Macie for multiple member accounts

Detailed Example 1: Discovering Credit Card Numbers in S3

Scenario: Your organization stores customer support tickets in S3, and you suspect some tickets may contain credit card numbers that customers accidentally included.

Using Macie to find credit cards:

  1. Enable Macie:

    • Enable Macie in the region where your S3 buckets are located
    • Macie immediately starts inventorying your S3 buckets
    • Within minutes, you see all buckets listed in the Macie console
  2. Review Automated Discovery Results:

    • Macie's automated discovery samples objects across all buckets
    • After 24-48 hours, Macie provides sensitivity scores for each bucket
    • "support-tickets" bucket shows high sensitivity score (likely contains PII)
    • "application-logs" bucket shows medium sensitivity score
    • "public-website" bucket shows low sensitivity score
  3. Create Sensitive Data Discovery Job:

    • Create a one-time job to scan the "support-tickets" bucket
    • Scope: All objects in the bucket
    • Managed data identifiers: Enable credit card detection
    • Sampling depth: 100% (full scan for accuracy)
    • Run the job
  4. Review Findings:

    • Job completes in 2 hours (scanned 50,000 objects)
    • Finding: Sensitive data detected in 127 objects
    • Data types found: Credit card numbers (Visa, Mastercard, Amex)
    • Sample occurrences:
      • Object: support-tickets/2024/ticket-12345.txt
      • Line 15: "My credit card number is 4532-1234-5678-9010"
      • Object: support-tickets/2024/ticket-67890.txt
      • Line 8: "Card: 5425-2334-3010-9903"
  5. Assess Risk:

    • 127 objects contain credit card numbers (0.25% of total objects)
    • All objects are in a private bucket (not publicly accessible)
    • Bucket has encryption enabled (SSE-S3)
    • However: Bucket policy allows broad access to multiple IAM roles
  6. Remediation Actions:

    • Implement least privilege: Restrict bucket access to only support team roles
    • Enable S3 Object Lock to prevent deletion of evidence
    • Create a Lambda function to automatically redact credit card numbers from new tickets
    • Implement input validation in support ticket system to reject credit card numbers
    • Notify affected customers that their credit card numbers were stored (compliance requirement)
    • Set up Macie scheduled job to scan new tickets daily

Why this works: Macie automatically scans thousands of objects to find sensitive data that would be impossible to find manually. The findings show exactly which objects contain credit cards, allowing targeted remediation.

Detailed Example 2: Detecting Publicly Accessible Buckets with Sensitive Data

Scenario: You want to ensure no S3 buckets containing sensitive data are publicly accessible.

Using Macie for security assessment:

  1. Enable Macie and Review Bucket Inventory:

    • Macie discovers 150 S3 buckets in your account
    • Dashboard shows: 3 buckets are publicly accessible
    • Dashboard shows: 45 buckets are not encrypted
  2. Investigate Public Buckets:

    • Bucket 1: "company-website" - Publicly accessible (expected, contains only public website files)
    • Bucket 2: "data-exports" - Publicly accessible (UNEXPECTED, should be private)
    • Bucket 3: "temp-storage" - Publicly accessible (UNEXPECTED, should be private)
  3. Run Sensitive Data Discovery on Public Buckets:

    • Create job to scan "data-exports" and "temp-storage" buckets
    • Enable all managed data identifiers
    • Run full scan (100% sampling)
  4. Review Findings:

    • "data-exports" bucket:
      • Contains 50 objects with email addresses
      • Contains 12 objects with phone numbers
      • Contains 3 objects with social security numbers (CRITICAL)
      • Bucket is publicly readable (anyone on the internet can access)
    • "temp-storage" bucket:
      • Contains 5 objects with AWS secret access keys (CRITICAL)
      • Contains 20 objects with email addresses
      • Bucket is publicly readable
  5. Assess Impact:

    • "data-exports": 3 SSNs exposed to the internet (data breach)
    • "temp-storage": 5 AWS secret keys exposed (security breach)
    • Check CloudTrail for unauthorized access to these buckets
    • Determine how long buckets were public (check Config timeline)
  6. Immediate Remediation:

    • Enable S3 Block Public Access on both buckets (blocks all public access)
    • Rotate all exposed AWS secret access keys immediately
    • Review CloudTrail for any API calls made with exposed keys
    • Delete sensitive objects from buckets or move to properly secured buckets
    • Enable bucket encryption (SSE-KMS with customer-managed key)
    • Implement bucket policies restricting access to specific IAM roles
  7. Long-Term Prevention:

    • Enable S3 Block Public Access at the account level (prevents future public buckets)
    • Use AWS Config rule to detect public buckets and automatically remediate
    • Set up Macie alerts to notify security team if new public buckets are created
    • Implement data classification policy requiring encryption for sensitive data
    • Train developers on secure S3 configuration

Why this works: Macie's bucket inventory immediately identifies security issues (public buckets, missing encryption), and sensitive data discovery confirms whether those buckets contain sensitive data, allowing you to prioritize remediation based on actual risk.

Detailed Example 3: Creating Custom Data Identifiers for Organization-Specific Data

Scenario: Your organization has internal employee IDs (format: EMP-123456) and customer account numbers (format: ACCT-XXXXXXXX) that you want to detect in S3.

Creating custom data identifiers:

  1. Define Employee ID Pattern:

    • Name: "Employee ID"
    • Regular expression: EMP-\d{6}
    • Keywords: ["employee", "staff", "personnel"]
    • Maximum match distance: 50 characters (keywords must be within 50 chars of pattern)
    • Ignore words: ["example", "sample", "test"]
  2. Define Customer Account Number Pattern:

    • Name: "Customer Account Number"
    • Regular expression: ACCT-[A-Z0-9]{8}
    • Keywords: ["customer", "account", "client"]
    • Maximum match distance: 50 characters
  3. Create Sensitive Data Discovery Job:

    • Scope: All buckets
    • Managed identifiers: Disabled (only use custom identifiers)
    • Custom identifiers: Enable "Employee ID" and "Customer Account Number"
    • Sampling: 10% (sample for efficiency)
    • Schedule: Weekly
  4. Review Findings:

    • Finding 1: Employee IDs found in "hr-documents" bucket (expected)
    • Finding 2: Employee IDs found in "application-logs" bucket (UNEXPECTED - logs should not contain employee IDs)
    • Finding 3: Customer account numbers found in "customer-data" bucket (expected)
    • Finding 4: Customer account numbers found in "public-website" bucket (CRITICAL - should not be public)
  5. Investigate Unexpected Findings:

    • Application logs with employee IDs:
      • Developers are logging employee IDs for debugging
      • Logs are retained for 1 year
      • Logs are accessible to entire development team
      • Risk: Employee IDs could be used for social engineering
    • Public website with customer account numbers:
      • Account numbers are embedded in URLs (e.g., /account/ACCT-12345678)
      • URLs are indexed by search engines
      • Risk: Account enumeration attack
  6. Remediation:

    • Application logs: Implement log sanitization to redact employee IDs before writing to S3
    • Public website: Change URL structure to use random UUIDs instead of account numbers
    • Monitoring: Set up Macie alerts to detect these patterns in new objects

Why this works: Custom data identifiers allow you to detect organization-specific sensitive data that managed identifiers don't cover. This ensures comprehensive data protection tailored to your business.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Macie scans all objects automatically"

    • Why it's wrong: Automated discovery uses sampling; you need to create jobs for comprehensive scans
    • Correct understanding: Automated discovery provides estimates; use jobs for accurate, complete scans
  • Mistake 2: "Macie prevents sensitive data from being uploaded to S3"

    • Why it's wrong: Macie is a detection service, not a prevention service
    • Correct understanding: Macie detects sensitive data after it's uploaded; use S3 Object Lambda or input validation to prevent uploads
  • Mistake 3: "Macie findings mean data was accessed by unauthorized parties"

    • Why it's wrong: Macie findings indicate sensitive data exists, not that it was accessed
    • Correct understanding: Use CloudTrail and S3 access logs to determine if sensitive data was actually accessed

🔗 Connections to Other Topics:

  • Relates to S3 Security because: Macie evaluates S3 bucket security configurations
  • Builds on Data Classification by: Automatically classifying data based on sensitivity
  • Often used with Compliance to: Demonstrate that sensitive data is properly protected

When to use (Comprehensive):

  • Use Macie when: You store sensitive data in S3 and need to know where it is
  • Use automated discovery when: You want continuous monitoring of all buckets
  • Use sensitive data jobs when: You need comprehensive scans of specific buckets
  • Use custom identifiers when: You have organization-specific sensitive data patterns
  • Don't use Macie when: You don't store data in S3 (Macie is S3-only)
  • Don't rely solely on sampling when: You need 100% accuracy for compliance (use full scans)

Limitations & Constraints:

  • S3-only: Macie only scans S3 buckets, not EBS, RDS, or other storage services
  • File type support: Best results with text files; limited support for binary formats
  • Object size limits: Objects larger than 20 GB are not scanned
  • Encrypted objects: Can scan SSE-S3 and SSE-KMS encrypted objects, but not client-side encrypted objects
  • Sampling limitations: Automated discovery samples ~5% of objects, may miss sensitive data
  • Cost: Charged per GB scanned and per bucket monitored

💡 Tips for Understanding:

  • Think of Macie as a data auditor: It finds sensitive data and security issues in S3
  • Start with automated discovery: Get a quick assessment before running expensive full scans
  • Use custom identifiers strategically: Only create them for truly organization-specific patterns
  • Integrate with Security Hub: Centralize Macie findings with other security findings

Amazon Inspector - Automated Vulnerability Management

What it is: Amazon Inspector is an automated vulnerability management service that continually scans AWS workloads for software vulnerabilities and unintended network exposure.

Why it exists: Manually tracking vulnerabilities across hundreds or thousands of EC2 instances, container images, and Lambda functions is impossible. New vulnerabilities are discovered daily (CVEs), and you need to know which of your resources are affected. Inspector automates vulnerability scanning and prioritizes findings based on risk.

Real-world analogy: Think of Inspector as a building inspector who continuously checks your property for structural issues, code violations, and safety hazards. Instead of waiting for an annual inspection, the inspector checks daily, immediately alerts you to new problems, and tells you which issues are most urgent based on their severity and whether they're actually exploitable.

How it works (Detailed step-by-step):

  1. Automatic Resource Discovery:

    • Inspector automatically discovers EC2 instances, ECR container images, and Lambda functions
    • No agents required for EC2 (uses Systems Manager SSM Agent)
    • Continuously monitors for new resources
    • Scans resources as soon as they're launched or deployed
  2. Vulnerability Scanning:

    • EC2 instances: Scans operating system packages for known CVEs
    • ECR container images: Scans container image layers for vulnerabilities
    • Lambda functions: Scans function code and dependencies for vulnerabilities
    • Uses CVE database (Common Vulnerabilities and Exposures)
    • Rescans automatically when new CVEs are published
  3. Network Reachability Analysis:

    • Analyzes network paths to EC2 instances
    • Identifies instances reachable from the internet
    • Evaluates security group rules, NACLs, route tables, internet gateways
    • Determines which ports are exposed and from where
    • Combines network exposure with vulnerability data for risk scoring
  4. Risk Scoring and Prioritization:

    • Inspector Risk Score: 0-10 scale (based on CVSS score)
    • Considers: Vulnerability severity, network exposure, exploit availability
    • Critical: Score 9.0-10.0 (immediate action required)
    • High: Score 7.0-8.9 (urgent remediation)
    • Medium: Score 4.0-6.9 (plan remediation)
    • Low: Score 0.1-3.9 (monitor)
    • Prioritizes findings that are both severe AND exploitable
  5. Findings and Remediation Guidance:

    • Detailed findings for each vulnerability
    • CVE ID, affected package, fixed version available
    • Remediation instructions (e.g., "Update package X to version Y")
    • Links to CVE details and vendor advisories
    • Integration with Security Hub for centralized management

📊 Inspector Vulnerability Scanning Diagram:

graph TB
    subgraph "AWS Resources"
        A[EC2 Instances]
        B[ECR Container Images]
        C[Lambda Functions]
    end
    
    subgraph "Inspector Service"
        D[Resource Discovery]
        E[CVE Database]
        F[Vulnerability Scanner]
        G[Network Reachability Analyzer]
        H[Risk Scoring Engine]
    end
    
    subgraph "Findings"
        I[Critical Vulnerabilities]
        J[High Vulnerabilities]
        K[Medium/Low Vulnerabilities]
        L[Network Exposure]
    end
    
    subgraph "Outputs"
        M[Inspector Console]
        N[Security Hub]
        O[EventBridge]
        P[Remediation Guidance]
    end
    
    A --> D
    B --> D
    C --> D
    
    D --> F
    E --> F
    D --> G
    
    F --> H
    G --> H
    
    H --> I
    H --> J
    H --> K
    G --> L
    
    I --> M
    J --> M
    K --> M
    L --> M
    
    I --> N
    J --> N
    K --> N
    L --> N
    
    I --> O
    J --> O
    
    M --> P
    
    style A fill:#e1f5fe
    style B fill:#e1f5fe
    style C fill:#e1f5fe
    style F fill:#fff9c4
    style G fill:#fff9c4
    style H fill:#fff9c4
    style I fill:#f44336
    style J fill:#ff9800
    style K fill:#ffeb3b
    style M fill:#c8e6c9
    style N fill:#c8e6c9
    style O fill:#c8e6c9

See: diagrams/02_domain1_inspector_scanning.mmd

Diagram Explanation (Detailed):

The Inspector Vulnerability Scanning diagram shows how Amazon Inspector continuously scans AWS resources for vulnerabilities. At the top (blue), three types of resources are monitored: EC2 Instances (virtual machines), ECR Container Images (Docker images), and Lambda Functions (serverless code). The Resource Discovery component automatically identifies all these resources in your account without requiring manual configuration. The Vulnerability Scanner analyzes each resource against the CVE Database (Common Vulnerabilities and Exposures), which contains information about all known security vulnerabilities. Simultaneously, the Network Reachability Analyzer examines network paths to determine which resources are exposed to the internet and which ports are open. The Risk Scoring Engine combines vulnerability severity with network exposure to calculate an Inspector Risk Score (0-10) for each finding. Findings are categorized by severity: Critical (red, score 9-10) requires immediate action, High (orange, score 7-8.9) needs urgent remediation, and Medium/Low (yellow, score 0.1-6.9) should be planned for remediation. Network Exposure findings identify resources that are internet-accessible. All findings are delivered to the Inspector Console for review, Security Hub for centralized management, and EventBridge for automated remediation. The Inspector Console provides Remediation Guidance with specific instructions on how to fix each vulnerability (e.g., which package to update and to which version). This architecture enables continuous vulnerability management without manual scanning or agent deployment.

Must Know (Critical Facts):

  • Inspector is always on - continuously scans resources, no manual scans needed
  • No agents required for EC2 - uses Systems Manager SSM Agent (must be installed)
  • Scans on push for ECR - automatically scans container images when pushed to ECR
  • Rescans automatically - when new CVEs are published, Inspector rescans all resources
  • Inspector Risk Score - 0-10 scale combining severity and exploitability
  • Regional service - must be enabled in each region where you have resources
  • Pricing: Per EC2 instance scanned, per container image scan, per Lambda function scanned

Detailed Example 1: Discovering Critical Vulnerability in EC2 Instance

Scenario: A new critical vulnerability (CVE-2024-12345) is published affecting the Apache web server. You have 50 EC2 instances running web servers.

How Inspector helps:

  1. Automatic Detection:

    • CVE-2024-12345 is added to the CVE database
    • Inspector automatically rescans all EC2 instances
    • Within 15 minutes, Inspector identifies 12 instances running vulnerable Apache version
  2. Finding Details:

    • Title: CVE-2024-12345 - Apache HTTP Server Remote Code Execution
    • Severity: Critical (CVSS score 9.8)
    • Inspector Risk Score: 9.8
    • Affected instances: 12 EC2 instances
    • Vulnerable package: apache2 version 2.4.41
    • Fixed version: apache2 version 2.4.52
    • Network exposure: 8 of 12 instances are internet-facing (port 80/443 open)
  3. Risk Assessment:

    • Critical risk: 8 instances are both vulnerable AND internet-accessible
    • Medium risk: 4 instances are vulnerable but in private subnets (not directly exploitable from internet)
    • Exploit available: Yes (public exploit code exists)
    • Priority: Immediate remediation required for internet-facing instances
  4. Remediation Steps (provided by Inspector):

    # For Ubuntu/Debian
    sudo apt-get update
    sudo apt-get install apache2=2.4.52
    sudo systemctl restart apache2
    
    # For Amazon Linux
    sudo yum update httpd
    sudo systemctl restart httpd
    
  5. Automated Remediation (optional):

    • Create EventBridge rule matching Critical Inspector findings
    • Trigger Systems Manager Automation document
    • Automation document:
      • Creates snapshot of instance for rollback
      • Updates Apache package
      • Restarts Apache service
      • Verifies service is running
      • Updates finding status in Inspector
  6. Verification:

    • Inspector rescans instances after remediation
    • Confirms Apache version is now 2.4.52
    • Finding status changes from ACTIVE to CLOSED
    • Security Hub shows reduced vulnerability count

Why this works: Inspector automatically detects new vulnerabilities across all your resources and prioritizes them based on actual risk (severity + exploitability + network exposure). You don't need to manually track CVEs or scan instances.

Detailed Example 2: Securing Container Images in ECR

Scenario: Your development team pushes container images to ECR daily. You need to ensure no vulnerable images are deployed to production.

Using Inspector for container security:

  1. Enable Inspector for ECR:

    • Inspector automatically scans all images pushed to ECR
    • Scan on push: Images are scanned immediately when pushed
    • Continuous scanning: Images are rescanned when new CVEs are published
  2. Developer Pushes Image:

    docker build -t myapp:v1.2.3 .
    docker tag myapp:v1.2.3 123456789012.dkr.ecr.us-east-1.amazonaws.com/myapp:v1.2.3
    docker push 123456789012.dkr.ecr.us-east-1.amazonaws.com/myapp:v1.2.3
    
  3. Inspector Scan Results:

    • Scan completes in 2 minutes
    • Findings: 15 vulnerabilities detected
      • 2 Critical (CVSS 9.0+)
      • 5 High (CVSS 7.0-8.9)
      • 8 Medium (CVSS 4.0-6.9)
    • Critical vulnerability 1: OpenSSL 1.1.1k (CVE-2024-XXXXX)
    • Critical vulnerability 2: Python 3.8.5 (CVE-2024-YYYYY)
  4. Block Deployment (using ECR lifecycle policy + Lambda):

    • EventBridge rule triggers when Inspector finds Critical vulnerabilities
    • Lambda function:
      • Adds "VULNERABLE" tag to image
      • Sends notification to development team
      • Updates deployment pipeline to block images with "VULNERABLE" tag
    • Deployment pipeline checks image tags before deploying
    • Deployment fails with message: "Image contains critical vulnerabilities, cannot deploy"
  5. Developer Remediation:

    • Update Dockerfile to use newer base image:
      # Before
      FROM python:3.8.5-slim
      
      # After
      FROM python:3.11.6-slim
      
    • Update OpenSSL package:
      RUN apt-get update && apt-get install -y openssl=1.1.1w
      
    • Rebuild and push image
    • Inspector rescans automatically
    • No critical vulnerabilities found
    • Image is tagged "APPROVED"
    • Deployment proceeds
  6. Continuous Monitoring:

    • Inspector continues scanning the image even after deployment
    • If new CVE affects the image, Inspector generates new finding
    • EventBridge triggers alert to security team
    • Security team evaluates if deployed containers need to be updated

Why this works: Inspector's scan-on-push capability prevents vulnerable container images from being deployed to production. Continuous scanning ensures you're notified if deployed images become vulnerable due to newly discovered CVEs.

Detailed Example 3: Network Reachability Analysis

Scenario: You want to identify which EC2 instances are exposed to the internet and have known vulnerabilities.

Using Inspector's network reachability analysis:

  1. Enable Inspector:

    • Inspector automatically analyzes network paths to all EC2 instances
    • Evaluates: Security groups, NACLs, route tables, internet gateways, NAT gateways
  2. Network Reachability Findings:

    • Finding 1: Instance i-1234567890abcdef0 is reachable from the internet on port 22 (SSH)
      • Security group allows 0.0.0.0/0 on port 22
      • Instance is in public subnet with internet gateway
      • Risk: High (SSH should not be exposed to internet)
    • Finding 2: Instance i-0987654321fedcba0 is reachable from the internet on port 3389 (RDP)
      • Security group allows 0.0.0.0/0 on port 3389
      • Instance is in public subnet
      • Risk: High (RDP should not be exposed to internet)
    • Finding 3: Instance i-abcdef1234567890 is reachable from the internet on port 443 (HTTPS)
      • Security group allows 0.0.0.0/0 on port 443
      • Instance is in public subnet
      • Risk: Low (HTTPS exposure is expected for web servers)
  3. Combine with Vulnerability Data:

    • Inspector cross-references network exposure with vulnerability findings
    • Instance i-1234567890abcdef0:
      • Internet-accessible on SSH (port 22)
      • Has critical vulnerability in SSH daemon (CVE-2024-ZZZZZ)
      • Inspector Risk Score: 9.5 (critical vulnerability + internet exposure)
      • Priority: Immediate remediation
    • Instance i-0987654321fedcba0:
      • Internet-accessible on RDP (port 3389)
      • No vulnerabilities detected
      • Inspector Risk Score: 7.0 (network exposure risk)
      • Priority: Remediate network configuration
    • Instance i-abcdef1234567890:
      • Internet-accessible on HTTPS (port 443)
      • Has medium vulnerability in web server
      • Inspector Risk Score: 5.5 (medium vulnerability + expected exposure)
      • Priority: Plan remediation
  4. Remediation Actions:

    • Instance i-1234567890abcdef0 (Critical):
      • Remove security group rule allowing 0.0.0.0/0 on port 22
      • Add rule allowing SSH only from bastion host
      • Update SSH daemon to patched version
      • Verify finding is resolved
    • Instance i-0987654321fedcba0 (High):
      • Remove security group rule allowing 0.0.0.0/0 on port 3389
      • Use Systems Manager Session Manager for remote access instead of RDP
      • Verify finding is resolved
    • Instance i-abcdef1234567890 (Medium):
      • Update web server to patched version
      • Keep HTTPS exposure (required for web server)
      • Monitor for new vulnerabilities

Why this works: Inspector's network reachability analysis identifies which resources are actually exploitable from the internet. A vulnerability in a private subnet instance is lower risk than the same vulnerability in an internet-facing instance.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: "Inspector scans application code for vulnerabilities"

    • Why it's wrong: Inspector scans OS packages and dependencies, not custom application code
    • Correct understanding: Use CodeGuru or third-party SAST tools for application code scanning
  • Mistake 2: "Inspector requires agents on EC2 instances"

    • Why it's wrong: Inspector uses the Systems Manager SSM Agent, which is pre-installed on many AMIs
    • Correct understanding: Ensure SSM Agent is installed and running, but no separate Inspector agent is needed
  • Mistake 3: "Inspector findings mean resources are actively being exploited"

    • Why it's wrong: Inspector detects vulnerabilities, not active exploitation
    • Correct understanding: Use GuardDuty to detect active exploitation; Inspector identifies potential vulnerabilities

🔗 Connections to Other Topics:

  • Relates to Systems Manager because: Inspector uses SSM Agent for EC2 scanning
  • Builds on Security Hub by: Inspector findings are aggregated in Security Hub
  • Often used with Patch Management to: Identify which instances need patching

Section 2: Incident Response Planning and Implementation

AWS Config - Configuration Compliance and Change Tracking

What it is: AWS Config is a service that continuously monitors and records AWS resource configurations and allows you to automate the evaluation of recorded configurations against desired configurations.

Why it exists: You need to know: What resources exist in your account? How are they configured? Who changed what and when? Are resources compliant with your security policies? Config provides a complete inventory, configuration history, and compliance monitoring.

Real-world analogy: Think of Config as a security camera system with DVR that records everything happening in your environment. It not only shows you the current state (live camera feed) but also lets you rewind to see what changed, when it changed, and who changed it. It can also alert you when something changes in a way that violates your security policies.

How it works (Detailed step-by-step):

  1. Resource Discovery and Inventory:

    • Config discovers all supported AWS resources in your account
    • Creates a complete inventory of resources
    • Tracks relationships between resources (e.g., EC2 instance → Security Group → VPC)
    • Updates inventory as resources are created, modified, or deleted
  2. Configuration Recording:

    • Records configuration changes for each resource
    • Stores configuration snapshots in S3
    • Maintains configuration history (up to 7 years)
    • Captures: What changed, when it changed, who changed it (via CloudTrail integration)
  3. Config Rules - Compliance Evaluation:

    • Managed Rules: Pre-built rules for common compliance checks (e.g., "S3 buckets must have encryption enabled")
    • Custom Rules: Lambda functions that evaluate custom compliance logic
    • Rules evaluate resources: Continuously (on configuration change) or Periodically (every 1, 3, 6, 12, or 24 hours)
    • Generates compliance findings: COMPLIANT, NON_COMPLIANT, NOT_APPLICABLE
  4. Remediation:

    • Manual Remediation: View non-compliant resources and fix manually
    • Automatic Remediation: Trigger Systems Manager Automation documents to automatically fix non-compliant resources
    • Remediation Retries: Automatically retry remediation if it fails
  5. Configuration Timeline and Relationships:

    • View configuration timeline for any resource
    • See all changes made to a resource over time
    • Visualize relationships between resources
    • Useful for troubleshooting and incident investigation

Must Know (Critical Facts):

  • Config is a regional service - must be enabled in each region
  • Requires S3 bucket - Config stores configuration snapshots in S3
  • Requires SNS topic - Config sends notifications to SNS
  • Pricing: Per configuration item recorded + per rule evaluation
  • Config Rules run automatically - no manual triggering needed
  • Integrates with Security Hub - Config findings appear in Security Hub

Detailed Example: Detecting and Remediating Public S3 Buckets

Scenario: You want to ensure no S3 buckets are publicly accessible.

Using Config:

  1. Enable Config Rule: "s3-bucket-public-read-prohibited"
  2. Config evaluates all S3 buckets: Checks if any bucket allows public read access
  3. Finding: 3 buckets are NON_COMPLIANT (publicly readable)
  4. Automatic Remediation: Config triggers Systems Manager Automation document that:
    • Enables S3 Block Public Access on the bucket
    • Updates bucket policy to remove public access
    • Marks finding as COMPLIANT
  5. Notification: SNS sends alert to security team

Why this works: Config continuously monitors for configuration drift and automatically remediates non-compliant resources.

Designing Incident Response Plans

What it is: An incident response plan is a documented process for detecting, responding to, and recovering from security incidents.

Why it exists: When a security incident occurs, you need to act quickly and systematically. Without a plan, teams waste time figuring out what to do, who to contact, and how to contain the threat. A good incident response plan ensures fast, effective response.

Key Components of an Incident Response Plan:

  1. Preparation:

    • Enable logging and monitoring (CloudTrail, VPC Flow Logs, GuardDuty)
    • Set up alerting (Security Hub, EventBridge, SNS)
    • Define roles and responsibilities (who does what during an incident)
    • Create runbooks and playbooks for common scenarios
    • Establish communication channels (Slack, PagerDuty, email)
    • Prepare forensic tools and isolated environments
  2. Detection and Analysis:

    • Monitor for security events (GuardDuty findings, Security Hub alerts)
    • Triage findings by severity and impact
    • Determine if it's a real incident or false positive
    • Assess scope: What resources are affected? What data is at risk?
    • Classify incident type: Malware, data breach, DDoS, unauthorized access, etc.
  3. Containment:

    • Short-term containment: Isolate affected resources immediately
      • Change security groups to deny all traffic
      • Disable compromised IAM credentials
      • Snapshot affected resources for forensics
    • Long-term containment: Implement temporary fixes while planning full remediation
      • Deploy patches
      • Implement additional monitoring
      • Restrict access further
  4. Eradication:

    • Remove the threat completely
    • Delete malware, backdoors, unauthorized users
    • Patch vulnerabilities that were exploited
    • Verify threat is eliminated
  5. Recovery:

    • Restore systems to normal operation
    • Verify systems are clean and functioning properly
    • Monitor closely for signs of re-infection
    • Gradually restore access and services
  6. Post-Incident Activity:

    • Document what happened (timeline, actions taken, lessons learned)
    • Update incident response plan based on lessons learned
    • Implement preventive measures to avoid recurrence
    • Share findings with stakeholders

Detailed Example: Responding to Compromised EC2 Instance

Scenario: GuardDuty detects cryptocurrency mining on EC2 instance i-1234567890abcdef0.

Incident Response Process:

  1. Detection (Automated):

    • GuardDuty generates finding: "CryptoCurrency:EC2/BitcoinTool.B!DNS"
    • Finding sent to Security Hub
    • EventBridge rule triggers SNS notification
    • Security team receives alert via email and Slack
  2. Analysis (5 minutes):

    • Review GuardDuty finding details
    • Check Detective for investigation insights
    • Determine: Instance is compromised, running cryptocurrency miner
    • Assess scope: Only this one instance affected (so far)
    • Check CloudTrail: No unusual API calls from instance's IAM role
  3. Containment (10 minutes):

    • Isolate instance: Change security group to deny all inbound/outbound traffic
    • Preserve evidence: Create EBS snapshot of instance volumes
    • Disable IAM role: Detach IAM role from instance to prevent further API calls
    • Tag instance: Add tag "Status=Quarantined" for tracking
  4. Eradication (30 minutes):

    • Forensic analysis: Mount snapshot to forensic instance
    • Identify malware: Find cryptocurrency miner binary in /tmp/
    • Determine entry point: SSH brute force attack (weak password)
    • Decision: Terminate compromised instance (cannot trust it)
  5. Recovery (1 hour):

    • Launch new instance: From clean AMI
    • Harden configuration:
      • Use SSH keys instead of passwords
      • Restrict SSH to bastion host only (not 0.0.0.0/0)
      • Enable fail2ban to block brute force attempts
      • Install security monitoring agent
    • Restore application: Deploy application from source control
    • Verify functionality: Test application works correctly
  6. Post-Incident (Next day):

    • Document incident: Create incident report with timeline
    • Lessons learned:
      • Weak SSH passwords enabled brute force attack
      • Security group allowed SSH from anywhere (0.0.0.0/0)
      • No fail2ban or rate limiting on SSH
    • Preventive measures:
      • Audit all EC2 instances for weak SSH configurations
      • Implement Config rule to detect security groups allowing SSH from 0.0.0.0/0
      • Mandate SSH key-based authentication (disable password auth)
      • Deploy fail2ban on all instances
    • Update runbook: Add cryptocurrency mining response to playbook

Why this works: Systematic incident response ensures nothing is missed, evidence is preserved, and the threat is completely eliminated.

Automated Incident Response with EventBridge and Lambda

What it is: Using EventBridge rules and Lambda functions to automatically respond to security findings without human intervention.

Why it exists: Manual incident response is slow. By the time a human reviews an alert and takes action, damage may already be done. Automated response can contain threats in seconds, not minutes or hours.

Common Automation Patterns:

  1. Isolate Compromised EC2 Instance:

    • Trigger: GuardDuty finding with severity HIGH or CRITICAL
    • Action: Lambda function changes instance security group to deny all traffic
    • Benefit: Immediate containment, prevents lateral movement
  2. Revoke Compromised IAM Credentials:

    • Trigger: GuardDuty finding indicating credential compromise
    • Action: Lambda function disables IAM access keys and terminates active sessions
    • Benefit: Stops attacker from using stolen credentials
  3. Block Malicious IP Addresses:

    • Trigger: GuardDuty finding with malicious IP address
    • Action: Lambda function adds IP to WAF IP set or Network Firewall deny list
    • Benefit: Blocks attacker at network perimeter
  4. Remediate Non-Compliant Resources:

    • Trigger: Config rule evaluation finds non-compliant resource
    • Action: Systems Manager Automation document fixes the configuration
    • Benefit: Automatic compliance enforcement

Detailed Example: Automated Response to Compromised Credentials

Architecture:

GuardDuty Finding → EventBridge Rule → Lambda Function → IAM API
                                    → SNS Topic → Security Team

EventBridge Rule:

{
  "source": ["aws.guardduty"],
  "detail-type": ["GuardDuty Finding"],
  "detail": {
    "severity": [7, 8, 9, 10],
    "type": ["UnauthorizedAccess:IAMUser/InstanceCredentialExfiltration"]
  }
}

Lambda Function (Python):

import boto3
import json

iam = boto3.client('iam')
sns = boto3.client('sns')

def lambda_handler(event, context):
    # Extract IAM user from finding
    finding = event['detail']
    resource = finding['resource']
    iam_user = resource['accessKeyDetails']['userName']
    access_key_id = resource['accessKeyDetails']['accessKeyId']
    
    # Disable access key
    iam.update_access_key(
        UserName=iam_user,
        AccessKeyId=access_key_id,
        Status='Inactive'
    )
    
    # Terminate all active sessions
    iam.delete_login_profile(UserName=iam_user)
    
    # Send notification
    sns.publish(
        TopicArn='arn:aws:sns:us-east-1:123456789012:security-alerts',
        Subject=f'URGENT: Compromised credentials for {iam_user}',
        Message=f'Access key {access_key_id} has been disabled. User sessions terminated.'
    )
    
    return {
        'statusCode': 200,
        'body': json.dumps(f'Remediated compromised credentials for {iam_user}')
    }

What happens:

  1. GuardDuty detects compromised credentials (10:00:00 AM)
  2. EventBridge rule matches finding (10:00:01 AM)
  3. Lambda function executes (10:00:02 AM)
  4. Access key disabled (10:00:03 AM)
  5. Sessions terminated (10:00:04 AM)
  6. SNS notification sent (10:00:05 AM)
  7. Total time: 5 seconds from detection to remediation

Why this works: Automated response is 100x faster than manual response. Attacker has only seconds to act before credentials are revoked.

Chapter Summary

What We Covered

Threat Detection Services:

  • GuardDuty: Intelligent threat detection using ML and threat intelligence
  • Security Hub: Centralized security findings and compliance management
  • Detective: Security investigation and root cause analysis
  • Macie: Sensitive data discovery and S3 security assessment
  • Inspector: Automated vulnerability management for EC2, ECR, Lambda
  • Config: Configuration compliance and change tracking

Incident Response:

  • Incident response plan components (Preparation, Detection, Containment, Eradication, Recovery, Post-Incident)
  • Automated response with EventBridge and Lambda
  • Common automation patterns for security incidents

Critical Takeaways

  1. GuardDuty is your first line of defense: Enable it in all regions for continuous threat detection
  2. Security Hub centralizes everything: Aggregate findings from all security services in one place
  3. Detective helps you investigate: Use it to understand the scope and root cause of incidents
  4. Macie protects sensitive data: Scan S3 buckets to find and protect PII, credit cards, etc.
  5. Inspector finds vulnerabilities: Continuously scan for CVEs in EC2, containers, and Lambda
  6. Config tracks changes: Know what changed, when, and who changed it
  7. Automate incident response: Use EventBridge + Lambda for immediate threat containment

Self-Assessment Checklist

Test yourself before moving on:

  • Can you explain what GuardDuty detects and how it works?
  • Can you describe the difference between GuardDuty and Security Hub?
  • Can you explain when to use Detective vs. GuardDuty?
  • Can you list 3 types of sensitive data Macie can detect?
  • Can you explain how Inspector prioritizes vulnerabilities?
  • Can you describe the 6 phases of incident response?
  • Can you design an automated response to a GuardDuty finding?

If you answered "no" to any of these, review the relevant section before proceeding.

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-35 (Threat Detection)
  • Domain 1 Bundle 2: Questions 36-70 (Incident Response)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections on services you got wrong
  • Focus on understanding WHEN to use each service
  • Practice distinguishing between similar services (GuardDuty vs. Detective, Macie vs. Inspector)

Quick Reference Card

Threat Detection Services:

  • GuardDuty: Detects threats (malware, compromised credentials, unusual API calls)
  • Security Hub: Aggregates findings, runs compliance checks
  • Detective: Investigates incidents, root cause analysis
  • Macie: Finds sensitive data in S3
  • Inspector: Scans for vulnerabilities (CVEs)
  • Config: Tracks configuration changes, compliance

When to Use:

  • Threat detection → GuardDuty
  • Centralized management → Security Hub
  • Investigation → Detective
  • Sensitive data → Macie
  • Vulnerabilities → Inspector
  • Configuration compliance → Config

Incident Response:

  1. Detect (GuardDuty, Security Hub)
  2. Analyze (Detective, CloudTrail)
  3. Contain (Isolate resources, disable credentials)
  4. Eradicate (Remove threat, patch vulnerabilities)
  5. Recover (Restore services, verify clean)
  6. Learn (Document, improve)

Chapter 1 Complete

Next Chapter: 03_domain2_logging_monitoring - Security Logging and Monitoring (18% of exam)


Chapter Summary

What We Covered

This chapter covered Domain 1: Threat Detection and Incident Response (14% of exam), including:

  • Incident Response Planning: Credential rotation, resource isolation, playbooks, security service deployment
  • Threat Detection: GuardDuty, Security Hub, Macie, Inspector, Config, Detective, IAM Access Analyzer
  • Anomaly Detection: CloudWatch metrics, Detective behavior graphs, Athena queries
  • Incident Response: Automated remediation, forensic data capture, root cause analysis
  • Security Automation: EventBridge, Lambda, Step Functions, Systems Manager

Critical Takeaways

  1. GuardDuty: Continuous threat detection using ML, analyzes VPC Flow Logs, DNS logs, CloudTrail
  2. Security Hub: Centralized security findings aggregation, compliance checks, automated remediation
  3. Detective: Visual investigation tool, behavior graphs, root cause analysis
  4. Macie: Sensitive data discovery in S3, PII detection, data classification
  5. Inspector: Vulnerability scanning for EC2 and containers, CVE detection
  6. Automated Response: EventBridge + Lambda for immediate threat response
  7. Forensics: EBS snapshots, memory dumps, isolated forensic accounts

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between GuardDuty, Security Hub, and Detective
  • I understand when to use each threat detection service
  • I can design an automated incident response workflow
  • I know how to isolate compromised resources
  • I understand forensic data capture techniques
  • I can explain how to rotate compromised credentials
  • I know how to use Detective for root cause analysis
  • I understand ASFF format and EventBridge integration
  • I can design a multi-account threat detection strategy
  • I know how to protect forensic artifacts

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-25 (Incident Response focus)
  • Domain 1 Bundle 2: Questions 26-50 (Threat Detection focus)
  • Threat Detection Services Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: Automated remediation, Detective investigation, Forensic capture
  • Focus on: Service selection criteria, integration patterns, automation workflows

Quick Reference Card

Key Services:

  • GuardDuty: Threat detection (malware, compromised credentials, unusual API calls)
  • Security Hub: Centralized findings, compliance checks, automated remediation
  • Detective: Investigation, behavior graphs, root cause analysis
  • Macie: Sensitive data discovery in S3
  • Inspector: Vulnerability scanning (EC2, containers)
  • Config: Configuration tracking, compliance monitoring

Decision Points:

  • Need threat detection? → GuardDuty
  • Need centralized security management? → Security Hub
  • Need to investigate incidents? → Detective
  • Need to find sensitive data? → Macie
  • Need vulnerability scanning? → Inspector
  • Need configuration compliance? → Config

Automation Pattern:

  1. GuardDuty/Security Hub detects threat
  2. EventBridge receives finding
  3. Lambda/Step Functions executes response
  4. Systems Manager applies remediation
  5. CloudTrail logs all actions

Chapter 1 Complete

Next Chapter: 03_domain2_logging_monitoring - Security Logging and Monitoring (18% of exam)


Chapter Summary

What We Covered

This chapter explored the critical domain of Threat Detection and Incident Response, covering:

Incident Response Planning: Designing comprehensive incident response plans with credential rotation strategies, resource isolation techniques, playbooks and runbooks, and integration of AWS security services (GuardDuty, Security Hub, Macie, Inspector, Config, Detective, IAM Access Analyzer).

Threat Detection: Detecting security threats and anomalies using AWS managed security services, correlating findings across services with Detective, validating security events with Athena queries, and creating CloudWatch metric filters and dashboards for anomaly detection.

Incident Response: Responding to compromised resources through automated remediation (Lambda, Step Functions, EventBridge, Systems Manager), conducting root cause analysis with Detective, capturing forensic data (EBS snapshots, memory dumps), and protecting forensic artifacts with S3 Object Lock and isolated accounts.

Critical Takeaways

  1. Automated Response is Essential: Manual incident response is too slow for cloud environments. Use EventBridge, Lambda, and Step Functions to automate detection and remediation workflows.

  2. Defense in Depth: Layer multiple security services (GuardDuty for threat detection, Security Hub for centralized findings, Detective for investigation, Config for compliance) to create comprehensive protection.

  3. Preserve Evidence First: When responding to incidents, always capture forensic evidence (snapshots, logs, memory dumps) before remediation. Use S3 Object Lock and isolated forensic accounts to ensure evidence integrity.

  4. Correlation is Key: Individual security findings are less valuable than correlated patterns. Use Detective's behavior graphs and Athena queries to connect events across services and identify attack patterns.

  5. Credential Rotation is Critical: Compromised credentials are the #1 attack vector. Implement automated rotation with Secrets Manager and immediate invalidation strategies for suspected compromises.

  6. Isolation Over Deletion: When resources are compromised, isolate them (change security groups, move to quarantine VPC) rather than deleting them. This preserves evidence and allows investigation.

  7. ASFF Standardization: Use AWS Security Finding Format (ASFF) to standardize security findings across services and enable automated processing and integration with third-party tools.

  8. Multi-Account Strategy: Implement separate forensic accounts for evidence storage, separate security tooling accounts for centralized monitoring, and use Organizations for cross-account security management.

Self-Assessment Checklist

Test yourself before moving on:

  • I can design an incident response plan with automated credential rotation and resource isolation
  • I understand how to deploy and configure GuardDuty, Security Hub, Macie, Inspector, Config, and Detective
  • I can explain how to integrate security services using EventBridge and ASFF
  • I can evaluate and prioritize findings from multiple security services
  • I understand how to use Detective to correlate security events and investigate threats
  • I can write Athena queries to validate security events in CloudTrail and VPC Flow Logs
  • I can create CloudWatch metric filters and alarms to detect anomalies
  • I can design automated remediation workflows using Lambda, Step Functions, and Systems Manager
  • I understand how to respond to compromised EC2 instances, IAM roles, S3 buckets, and RDS instances
  • I can conduct root cause analysis using Detective's behavior graphs and timeline analysis
  • I know how to capture forensic data (EBS snapshots, memory dumps, network traffic)
  • I can protect forensic artifacts using S3 Object Lock, isolated accounts, and lifecycle policies
  • I understand the difference between isolation and deletion when responding to incidents

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-25 (Incident Response Planning & Threat Detection)
  • Domain 1 Bundle 2: Questions 26-50 (Incident Response & Forensics)
  • Incident Response Bundle: All 50 questions (Cross-domain incident response scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections on automated remediation workflows (Task 1.3)
  • Focus on Detective investigation techniques and behavior graphs
  • Practice writing Athena queries for security event validation
  • Study forensic data capture and evidence preservation techniques

Quick Reference Card

Key Services:

  • GuardDuty: Threat detection using ML, analyzes VPC Flow Logs, DNS logs, CloudTrail
  • Security Hub: Centralized security findings aggregation and compliance checks
  • Detective: Investigation and root cause analysis using behavior graphs
  • Macie: Sensitive data discovery and classification in S3
  • Inspector: Vulnerability scanning for EC2 and container images
  • Config: Resource configuration tracking and compliance monitoring
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • ASFF: AWS Security Finding Format for standardized security findings
  • Behavior Graph: Detective's visual representation of resource relationships and activities
  • Forensic Isolation: Isolating compromised resources while preserving evidence
  • Automated Remediation: Using EventBridge, Lambda, and Step Functions for automated response

Decision Points:

  • Credential compromise → Rotate immediately with Secrets Manager, invalidate sessions with IAM
  • EC2 compromise → Isolate with security groups, capture snapshot and memory dump, investigate with Detective
  • S3 data exfiltration → Enable GuardDuty S3 protection, review CloudTrail for API calls, use Macie to identify sensitive data
  • Multi-service threat → Use Security Hub to aggregate findings, Detective to correlate events, Athena to validate

Exam Tips:

  • Questions often test automated response workflows (EventBridge → Lambda → remediation)
  • Know the difference between GuardDuty (detection), Detective (investigation), and Security Hub (aggregation)
  • Understand when to use Athena vs CloudWatch Logs Insights for log analysis
  • Remember that forensic evidence must be preserved before remediation
  • Multi-account scenarios require delegated administration and cross-account roles


Chapter Summary

What We Covered

This chapter explored AWS threat detection and incident response capabilities across three critical areas:

Incident Response Planning

  • Credential invalidation and rotation strategies using IAM and Secrets Manager
  • Resource isolation techniques for compromised workloads
  • Automated playbooks and runbooks with Systems Manager and Step Functions
  • Security service deployment (GuardDuty, Security Hub, Macie, Inspector, Config, Detective)
  • Integration patterns using EventBridge and ASFF

Threat Detection and Anomaly Analysis

  • Evaluating findings from multiple security services
  • Correlating threats across services using Detective
  • Validating security events with Athena queries
  • Creating metric filters and dashboards in CloudWatch
  • Identifying anomalies through behavior analysis

Incident Response and Remediation

  • Automating remediation with Lambda, Step Functions, and EventBridge
  • Responding to compromised EC2 instances, IAM roles, and S3 buckets
  • Conducting root cause analysis with Detective
  • Capturing forensic data (EBS snapshots, memory dumps, network traffic)
  • Protecting forensic artifacts with S3 Object Lock and isolated accounts

Critical Takeaways

  1. GuardDuty is the foundation: Enable GuardDuty in all accounts and regions for continuous threat detection using machine learning and threat intelligence
  2. Security Hub centralizes findings: Aggregate findings from all security services into Security Hub for unified visibility and automated response
  3. Detective accelerates investigations: Use Detective's behavior graphs to quickly identify root causes and understand attack scope
  4. Automate everything: Use EventBridge rules to trigger automated responses via Lambda or Step Functions for common security events
  5. Isolate first, investigate later: When compromise is detected, immediately isolate the resource to prevent lateral movement, then conduct forensics
  6. Preserve evidence: Use S3 Object Lock in compliance mode and isolated forensic accounts to ensure evidence integrity
  7. Credential rotation is critical: Implement automated credential rotation for all IAM users, access keys, and secrets
  8. ASFF enables integration: Use AWS Security Finding Format to integrate third-party security tools with AWS native services
  9. Macie protects sensitive data: Enable Macie to discover and classify sensitive data in S3 buckets automatically
  10. Inspector scans for vulnerabilities: Use Inspector to continuously scan EC2 instances and container images for software vulnerabilities

Self-Assessment Checklist

Test yourself before moving on:

Incident Response Planning:

  • I can explain how to invalidate compromised IAM credentials automatically
  • I understand how to isolate a compromised EC2 instance using security groups and NACLs
  • I can design an incident response playbook using Systems Manager Automation
  • I know the differences between GuardDuty, Security Hub, Macie, Inspector, Config, and Detective
  • I understand how to integrate security services using EventBridge and ASFF

Threat Detection:

  • I can interpret GuardDuty findings and determine appropriate responses
  • I understand how to use Detective to investigate security incidents
  • I can write Athena queries to analyze CloudTrail logs for suspicious activity
  • I know how to create CloudWatch metric filters to detect anomalies
  • I can correlate findings across multiple security services

Incident Response:

  • I can design automated remediation workflows using Lambda and Step Functions
  • I understand how to respond to different types of compromises (EC2, IAM, S3, RDS, Lambda)
  • I know how to capture forensic evidence (snapshots, memory dumps, network traffic)
  • I can protect forensic artifacts using S3 Object Lock and isolated accounts
  • I understand the complete incident response lifecycle from detection to recovery

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-25 (Incident Response Planning)
  • Domain 1 Bundle 2: Questions 26-50 (Threat Detection and Response)
  • Threat Detection Services Bundle: Questions 1-50 (Service-specific scenarios)
  • Incident Response Bundle: Questions 1-50 (End-to-end scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections on services where you missed questions
  • Focus on understanding the "when to use" decision frameworks
  • Practice more Athena queries and CloudWatch metric filters
  • Review the automated remediation patterns and workflows

Quick Reference Card

Key Services:

  • GuardDuty: Continuous threat detection using ML and threat intelligence
  • Security Hub: Centralized security findings aggregation and compliance checks
  • Detective: Visual investigation tool with behavior graphs for root cause analysis
  • Macie: Sensitive data discovery and classification in S3
  • Inspector: Vulnerability scanning for EC2 and container images
  • Config: Resource configuration tracking and compliance monitoring
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • ASFF: AWS Security Finding Format for standardized security findings
  • Isolation: Immediately isolate compromised resources to prevent lateral movement
  • Forensics: Capture evidence before remediation (snapshots, logs, memory dumps)
  • Automation: Use EventBridge + Lambda/Step Functions for automated response
  • Credential Rotation: Automate rotation of IAM credentials and secrets

Decision Points:

  • Threat detected → Isolate → Investigate → Remediate → Recover
  • GuardDuty finding → EventBridge rule → Lambda/Step Functions → Automated action
  • Sensitive data exposure → Macie finding → S3 bucket policy update → Notification
  • Vulnerability detected → Inspector finding → Systems Manager patch → Verification
  • Incident investigation → Detective behavior graph → Root cause → Remediation plan

Remediation Workflow:

  • Compromised resource → Isolate → Investigate → Remediate → Document

Chapter Summary

What We Covered

This chapter covered the critical domain of Threat Detection and Incident Response, which accounts for 14% of the SCS-C02 exam. We explored three major task areas:

Task 1.1: Incident Response Planning

  • Credential invalidation and rotation strategies using IAM, Secrets Manager, and automated workflows
  • Resource isolation techniques for compromised EC2 instances, IAM roles, and other AWS resources
  • Designing and implementing incident response playbooks and runbooks
  • Deploying and configuring security services (GuardDuty, Security Hub, Macie, Inspector, Config, Detective, IAM Access Analyzer)
  • Integrating security services with EventBridge and using AWS Security Finding Format (ASFF)

Task 1.2: Threat Detection and Anomaly Detection

  • Evaluating findings from GuardDuty, Security Hub, Macie, Config, and IAM Access Analyzer
  • Using Detective for threat correlation and investigation with behavior graphs
  • Validating security events using Athena queries on CloudTrail and VPC Flow Logs
  • Creating CloudWatch metric filters, alarms, and dashboards for anomaly detection

Task 1.3: Responding to Compromised Resources

  • Automating remediation using Lambda, Step Functions, EventBridge, and Systems Manager
  • Responding to compromised EC2 instances, IAM roles, S3 buckets, RDS instances, and Lambda functions
  • Conducting root cause analysis using Detective's investigation capabilities
  • Capturing forensic evidence (EBS snapshots, memory dumps, network traffic)
  • Protecting and preserving forensic artifacts using S3 Object Lock, isolated accounts, and lifecycle policies

Critical Takeaways

  1. Automated Response is Essential: Manual incident response is too slow for cloud environments. Use EventBridge + Lambda/Step Functions for automated detection and response workflows.

  2. Isolation First, Investigation Second: When a resource is compromised, immediately isolate it to prevent lateral movement. Capture forensic evidence before remediation.

  3. Security Hub is the Central Hub: Security Hub aggregates findings from all security services (GuardDuty, Macie, Inspector, Config, IAM Access Analyzer) and provides a unified view.

  4. Detective Accelerates Investigations: Detective's behavior graphs and visualizations dramatically reduce investigation time by showing relationships between entities and activities.

  5. Forensics Requires Planning: You can't capture forensic evidence if you haven't configured logging and snapshots in advance. Enable CloudTrail, VPC Flow Logs, and automated snapshots before incidents occur.

  6. ASFF Enables Integration: The AWS Security Finding Format (ASFF) standardizes security findings, making it easy to integrate AWS security services with third-party tools.

  7. Credential Rotation is Continuous: Credential rotation isn't a one-time activity. Use Secrets Manager for automatic rotation and implement detection for long-lived credentials.

  8. Athena is Your Threat Hunting Tool: For deep investigation, use Athena to query CloudTrail logs, VPC Flow Logs, and other log sources stored in S3.

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Incident Response Planning:

  • Explain how to automatically rotate compromised credentials using Secrets Manager
  • Describe the steps to isolate a compromised EC2 instance (security groups, NACLs, snapshot)
  • Design an incident response playbook using EventBridge, Lambda, and Step Functions
  • Configure GuardDuty to send findings to Security Hub and trigger automated responses
  • Explain the purpose and structure of AWS Security Finding Format (ASFF)

Threat Detection:

  • Interpret GuardDuty findings and determine appropriate response actions
  • Use Detective to investigate suspicious activity and identify root causes
  • Write Athena queries to search CloudTrail logs for specific API calls
  • Create CloudWatch metric filters to detect failed login attempts or unusual API activity
  • Explain how Security Hub aggregates findings from multiple security services

Incident Response:

  • Design an automated remediation workflow for a compromised IAM role
  • Explain how to capture forensic evidence from a compromised EC2 instance
  • Use Detective to trace the timeline of a security incident
  • Describe how to protect forensic artifacts using S3 Object Lock
  • Implement automated isolation using Lambda and EventBridge

Decision-Making:

  • Choose between GuardDuty, Security Hub, and Detective for different security scenarios
  • Determine when to use Secrets Manager vs. Systems Manager Parameter Store
  • Decide between Lambda and Step Functions for remediation workflows
  • Select appropriate isolation techniques based on resource type and threat severity

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-35 (focus on incident response planning and threat detection)
  • Domain 1 Bundle 2: Questions 36-70 (focus on automated remediation and forensics)
  • Threat Detection Services Bundle: Questions covering GuardDuty, Security Hub, Detective, Macie
  • Incident Response Bundle: Questions covering automated response workflows

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • Automated Remediation Workflows (if you struggled with Lambda/Step Functions questions)
    • Detective Investigation Process (if you struggled with root cause analysis)
    • Forensic Evidence Capture (if you struggled with snapshot and isolation questions)
  • Focus on:
    • Understanding the "when to use" decision frameworks for each security service
    • Practicing Athena queries for threat hunting
    • Memorizing the automated response patterns (EventBridge → Lambda → Action)

Next Steps

Before moving to Domain 2:

  1. Review the Quick Reference Card above and ensure you can recall all key services and concepts
  2. Practice writing EventBridge rules and Lambda functions for automated response
  3. Experiment with Detective (if you have access) to understand behavior graphs
  4. Complete at least one full practice test focused on Domain 1

Moving Forward:

  • Domain 2 (Security Logging and Monitoring) builds directly on Domain 1's concepts
  • You'll learn how to configure the logging sources that feed into threat detection services
  • Understanding CloudTrail, VPC Flow Logs, and CloudWatch is essential for effective threat detection

Chapter Summary

What We Covered

This chapter covered Domain 1: Threat Detection and Incident Response (14% of the exam), focusing on three critical task areas:

Task 1.1: Design and implement an incident response plan

  • Credential invalidation and rotation strategies using IAM and Secrets Manager
  • Resource isolation techniques for compromised EC2 instances and other resources
  • Incident response playbooks and runbooks using Systems Manager Automation
  • Security service deployment (GuardDuty, Security Hub, Macie, Inspector, Config, Detective, IAM Access Analyzer)
  • Integration with EventBridge and AWS Security Finding Format (ASFF)

Task 1.2: Detect security threats and anomalies

  • Evaluating findings from GuardDuty, Security Hub, Macie, Config, and IAM Access Analyzer
  • Searching and correlating threats using Detective behavior graphs
  • Validating security events using Athena queries on CloudTrail and VPC Flow Logs
  • Creating metric filters and dashboards in CloudWatch for anomaly detection

Task 1.3: Respond to compromised resources and workloads

  • Automating remediation using Lambda, Step Functions, EventBridge, and Systems Manager
  • Responding to compromised EC2 instances, IAM roles, S3 buckets, and other resources
  • Investigating and analyzing with Detective for root cause analysis
  • Capturing forensic data (EBS snapshots, memory dumps, network traffic)
  • Protecting and preserving forensic artifacts using S3 Object Lock and isolated accounts

Critical Takeaways

  1. GuardDuty is the foundation: It analyzes CloudTrail, VPC Flow Logs, and DNS logs to detect threats. Enable it in all accounts and regions.

  2. Security Hub aggregates findings: It collects findings from GuardDuty, Macie, Inspector, Config, IAM Access Analyzer, and third-party tools into a single dashboard.

  3. Detective investigates threats: Use it to visualize behavior graphs and understand the scope and timeline of security incidents.

  4. Automate response workflows: EventBridge + Lambda + Step Functions enable automated remediation without manual intervention.

  5. Isolate first, investigate later: When a resource is compromised, immediately isolate it (change security groups, revoke credentials) before starting forensics.

  6. Preserve forensic evidence: Take EBS snapshots, capture memory dumps, and store them in isolated accounts with S3 Object Lock to prevent tampering.

  7. Credential rotation is critical: Use Secrets Manager for automatic rotation of database credentials and IAM for access key rotation.

  8. Athena for threat hunting: Query CloudTrail and VPC Flow Logs in S3 using Athena to validate security events and hunt for threats.

  9. Macie finds sensitive data: Use it to discover PII, financial data, and credentials in S3 buckets, then remediate exposure.

  10. Inspector scans for vulnerabilities: Enable continuous scanning for EC2 instances and container images to detect software vulnerabilities.

Self-Assessment Checklist

Test yourself before moving to Domain 2. You should be able to:

Incident Response Planning:

  • Explain how to invalidate compromised IAM credentials (delete access keys, attach deny policy, revoke sessions)
  • Describe how to rotate database credentials using Secrets Manager
  • Design an automated incident response workflow using EventBridge, Lambda, and Step Functions
  • Explain when to use GuardDuty vs. Security Hub vs. Detective vs. Macie
  • Describe how to integrate third-party security tools using ASFF and EventBridge

Threat Detection:

  • Interpret GuardDuty findings and determine appropriate responses
  • Use Detective to investigate the scope and timeline of a security incident
  • Write Athena queries to search CloudTrail logs for specific API calls
  • Create CloudWatch metric filters to detect anomalous activity (e.g., root account usage)
  • Explain how Security Hub custom insights work

Incident Response:

  • Describe how to isolate a compromised EC2 instance (change security group, detach IAM role)
  • Explain how to capture forensic evidence (EBS snapshot, memory dump, network traffic)
  • Design an automated remediation workflow for common security findings
  • Describe how to protect forensic artifacts using S3 Object Lock and isolated accounts
  • Explain the difference between compliance mode and governance mode for S3 Object Lock

Service Integration:

  • Explain how GuardDuty, CloudTrail, and VPC Flow Logs work together
  • Describe how Security Hub aggregates findings from multiple sources
  • Explain how Detective uses CloudTrail and VPC Flow Logs to build behavior graphs
  • Describe how to trigger Lambda functions from Security Hub custom actions
  • Explain how Config rules can trigger automated remediation

Practice Questions

Recommended Practice Test Bundles:

  • Domain 1 Bundle 1: Questions 1-50 (covers all Task 1.1, 1.2, 1.3 topics)
  • Domain 1 Bundle 2: Questions 51-70 (additional practice on weak areas)
  • Threat Detection Services Bundle: Questions covering GuardDuty, Security Hub, Detective, Macie
  • Incident Response Bundle: Questions covering automated response workflows

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • Automated Remediation Workflows (if you struggled with Lambda/Step Functions questions)
    • Detective Investigation Process (if you struggled with root cause analysis)
    • Forensic Evidence Capture (if you struggled with snapshot and isolation questions)
  • Focus on:
    • Understanding the "when to use" decision frameworks for each security service
    • Practicing Athena queries for threat hunting
    • Memorizing the automated response patterns (EventBridge → Lambda → Action)
    • Understanding the difference between GuardDuty (detection), Security Hub (aggregation), and Detective (investigation)

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • GuardDuty: Threat detection using ML (analyzes CloudTrail, VPC Flow Logs, DNS logs)
  • Security Hub: Centralized security findings aggregation and compliance checks
  • Detective: Visual investigation tool using behavior graphs
  • Macie: Sensitive data discovery in S3 (PII, financial data, credentials)
  • Inspector: Vulnerability scanning for EC2 and container images
  • Config: Resource configuration tracking and compliance monitoring
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • ASFF: AWS Security Finding Format (standard JSON format for security findings)
  • Behavior Graph: Detective's visual representation of resource interactions over time
  • Forensic Isolation: Isolating compromised resources while preserving evidence
  • Automated Remediation: EventBridge + Lambda + Step Functions for automatic response
  • Credential Rotation: Secrets Manager (automatic) or IAM (manual)

Decision Points:

  • Threat detection → GuardDuty (enable in all accounts and regions)
  • Finding aggregation → Security Hub (centralized dashboard)
  • Incident investigation → Detective (behavior graphs and timelines)
  • Sensitive data discovery → Macie (S3 scanning)
  • Vulnerability scanning → Inspector (EC2 and containers)
  • Automated response → EventBridge + Lambda (event-driven)
  • Forensic evidence → EBS snapshots + S3 Object Lock (immutable storage)

Common Patterns:

  • GuardDuty finding → EventBridge → Lambda → Isolate resource
  • Security Hub finding → Custom action → Lambda → Remediate
  • Detective → Behavior graph → Identify scope → Respond
  • Macie → Sensitive data found → EventBridge → Lambda → Encrypt + Notify

Chapter 1 Complete

Next: Proceed to Chapter 2 (Domain 2: Security Logging and Monitoring) to learn how to configure the logging sources that feed into threat detection services.

Chapter Summary

What We Covered

This chapter covered Domain 1: Threat Detection and Incident Response (14% of the exam), focusing on three critical task areas:

Task 1.1: Design and implement an incident response plan

  • Credential invalidation and rotation strategies using IAM and Secrets Manager
  • Resource isolation techniques for compromised EC2 instances and accounts
  • Incident response playbooks and runbooks with Systems Manager and Step Functions
  • Security service deployment (GuardDuty, Security Hub, Macie, Inspector, Config, Detective, IAM Access Analyzer)
  • Integration with EventBridge and AWS Security Finding Format (ASFF)

Task 1.2: Detect security threats and anomalies

  • Evaluating findings from GuardDuty, Security Hub, Macie, Config, and IAM Access Analyzer
  • Searching and correlating threats using Detective's behavior graphs
  • Validating security events with Athena queries on CloudTrail and VPC Flow Logs
  • Creating CloudWatch metric filters, alarms, and dashboards for anomaly detection

Task 1.3: Respond to compromised resources and workloads

  • Automating remediation with Lambda, Step Functions, EventBridge, and Systems Manager
  • Responding to compromised EC2 instances, IAM roles, S3 buckets, and RDS databases
  • Conducting root cause analysis using Detective
  • Capturing forensic data (EBS snapshots, memory dumps, network traffic)
  • Protecting forensic artifacts with S3 Object Lock and isolated forensic accounts

Critical Takeaways

  1. GuardDuty is the foundation: It continuously monitors CloudTrail, VPC Flow Logs, and DNS logs for threats. Enable it in all accounts and regions.

  2. Security Hub centralizes findings: It aggregates findings from GuardDuty, Macie, Inspector, Config, IAM Access Analyzer, and third-party tools into a single dashboard.

  3. Detective investigates incidents: Use it to analyze behavior graphs, visualize relationships, and conduct root cause analysis after GuardDuty detects a threat.

  4. Automate incident response: Use EventBridge to trigger Lambda functions or Step Functions workflows that automatically isolate resources, rotate credentials, and notify teams.

  5. Preserve forensic evidence: Always create snapshots before remediation, use S3 Object Lock for immutability, and store artifacts in isolated forensic accounts.

  6. Credential rotation is critical: When credentials are compromised, immediately invalidate them, rotate to new credentials, and audit all actions taken with the compromised credentials.

  7. Isolation prevents lateral movement: Isolate compromised resources by modifying security groups, moving to quarantine subnets, or detaching from networks entirely.

  8. Athena enables threat hunting: Query CloudTrail and VPC Flow Logs in S3 using Athena to validate security events and search for indicators of compromise.

  9. CloudWatch detects anomalies: Create metric filters to count security events, set alarms for thresholds, and use anomaly detection for baseline deviations.

  10. ASFF standardizes findings: The AWS Security Finding Format provides a consistent structure for security findings, enabling integration with third-party SIEM and SOAR tools.

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Incident Response Planning:

  • Explain how to automatically rotate compromised IAM access keys using Lambda
  • Describe the steps to isolate a compromised EC2 instance without terminating it
  • Design an incident response playbook using Systems Manager Automation runbooks
  • Configure Security Hub to aggregate findings from multiple AWS accounts
  • Create an EventBridge rule that triggers remediation when GuardDuty detects a threat

Threat Detection:

  • Interpret GuardDuty finding types and severity levels
  • Explain how Detective builds behavior graphs from CloudTrail and VPC Flow Logs
  • Write an Athena query to find all API calls made by a specific IAM user
  • Create a CloudWatch metric filter to count failed SSH login attempts
  • Differentiate between GuardDuty, Security Hub, Macie, and Inspector

Incident Response:

  • Design an automated remediation workflow using Step Functions
  • Explain how to capture a memory dump from a compromised EC2 instance
  • Describe the process for creating forensic snapshots with proper chain of custody
  • Configure S3 Object Lock to prevent deletion of forensic evidence
  • Use Detective to investigate the timeline of a security incident

Integration and Automation:

  • Explain how ASFF enables integration with third-party security tools
  • Design a multi-account GuardDuty deployment with delegated administration
  • Create a custom Security Hub insight to track specific security metrics
  • Configure CloudWatch Logs Insights to search for security patterns
  • Implement automated credential rotation for RDS databases using Secrets Manager

Practice Questions

Try these from your practice test bundles:

  • Domain 1 Bundle 1: Questions 1-25 (focus on incident response planning)
  • Domain 1 Bundle 2: Questions 26-50 (focus on threat detection and response)
  • Threat Detection Services Bundle: Questions covering GuardDuty, Security Hub, Detective, Macie
  • Incident Response Bundle: Questions covering automated remediation and forensics

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections on services you struggled with (GuardDuty, Detective, Security Hub)
  • Focus on understanding the differences between detection services
  • Practice writing EventBridge rules and Lambda functions for automation
  • Revisit the incident response workflow diagrams

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • GuardDuty: Threat detection using ML on CloudTrail, VPC Flow Logs, DNS logs
  • Security Hub: Centralized security findings aggregation and compliance checks
  • Detective: Root cause analysis using behavior graphs and visualizations
  • Macie: Sensitive data discovery and classification in S3
  • Inspector: Vulnerability scanning for EC2 and container images
  • Config: Resource configuration tracking and compliance monitoring
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • ASFF: AWS Security Finding Format for standardized security findings
  • Behavior Graph: Detective's visualization of resource relationships and activities
  • Forensic Isolation: Isolating compromised resources while preserving evidence
  • Credential Rotation: Automatically replacing compromised credentials
  • Automated Remediation: Using EventBridge + Lambda/Step Functions to respond to threats

Decision Points:

  • Threat detected → GuardDuty finding → EventBridge rule → Lambda remediation
  • Need investigation → Detective behavior graph → Timeline analysis → Root cause
  • Sensitive data exposure → Macie finding → S3 bucket policy remediation
  • Compromised credentials → Invalidate immediately → Rotate → Audit usage
  • Compromised EC2 → Isolate (security group) → Snapshot (forensics) → Investigate

You're now ready for Chapter 2: Security Logging and Monitoring!

The next chapter will teach you how to configure the logging sources (CloudTrail, VPC Flow Logs, CloudWatch) that feed into the threat detection services you just learned about.


Chapter 2: Security Logging and Monitoring (18% of exam)

Chapter Overview

What you'll learn:

  • How to design and implement comprehensive logging solutions across AWS services
  • Monitoring and alerting strategies to detect security events in real-time
  • Log analysis techniques to identify threats and anomalies
  • Troubleshooting logging and monitoring issues
  • Best practices for log storage, retention, and lifecycle management

Time to complete: 10-12 hours
Prerequisites: Chapter 0 (Fundamentals), Chapter 1 (Threat Detection basics)

Why this domain matters: Logging and monitoring form the foundation of security visibility in AWS. Without proper logging, you cannot detect threats, investigate incidents, or prove compliance. This domain represents 18% of the exam and tests your ability to design complete logging architectures, troubleshoot missing logs, and analyze log data to find security issues.


Section 1: AWS CloudTrail - API Activity Logging

Introduction

The problem: In cloud environments, every action is an API call. Without tracking these calls, you have no audit trail of who did what, when, and from where. This makes it impossible to investigate security incidents, detect unauthorized access, or meet compliance requirements.

The solution: AWS CloudTrail records every API call made in your AWS account, creating a complete audit trail of all actions. It captures the identity of the caller, the time of the call, the source IP address, the request parameters, and the response elements.

Why it's tested: CloudTrail is fundamental to AWS security. The exam tests your understanding of how to configure CloudTrail properly, troubleshoot missing logs, analyze CloudTrail data, and integrate it with other security services.

Core Concepts

What is CloudTrail

What it is: CloudTrail is a service that records API calls made in your AWS account and delivers log files to an S3 bucket. It tracks management events (control plane operations like creating EC2 instances) and optionally data events (data plane operations like reading S3 objects).

Why it exists: Every action in AWS is an API call - whether you use the console, CLI, SDK, or another service. CloudTrail provides accountability by recording who made each call, enabling security investigations, compliance auditing, and operational troubleshooting.

Real-world analogy: CloudTrail is like a security camera system for your AWS account. Just as cameras record who enters a building and what they do, CloudTrail records who accesses your AWS resources and what actions they perform.

How it works (Detailed step-by-step):

  1. API Call Made: A user, service, or application makes an API call to AWS (e.g., ec2:RunInstances to launch an EC2 instance).
  2. CloudTrail Captures Event: CloudTrail intercepts the API call and records details including the caller identity (IAM user, role, or service), timestamp, source IP address, request parameters, and response.
  3. Event Aggregation: CloudTrail aggregates events from all AWS services in the region (or globally for multi-region trails) into log files.
  4. Log File Creation: Every 5-15 minutes, CloudTrail creates a JSON log file containing all captured events during that period.
  5. Delivery to S3: CloudTrail delivers the log file to your designated S3 bucket, optionally encrypting it with KMS.
  6. Optional SNS Notification: If configured, CloudTrail publishes an SNS notification when a new log file is delivered.
  7. Log File Validation: CloudTrail creates digest files that allow you to verify log file integrity and detect tampering.

📊 CloudTrail Architecture Diagram:

graph TB
    subgraph "AWS Account"
        subgraph "Region 1"
            API1[API Calls]
            CT1[CloudTrail Service]
        end
        subgraph "Region 2"
            API2[API Calls]
            CT2[CloudTrail Service]
        end
        subgraph "Global Services"
            IAM[IAM/STS/CloudFront]
        end
    end
    
    S3[S3 Bucket<br/>Log Storage]
    KMS[KMS Key<br/>Encryption]
    SNS[SNS Topic<br/>Notifications]
    CW[CloudWatch Logs<br/>Real-time Analysis]
    
    API1 --> CT1
    API2 --> CT2
    IAM --> CT1
    
    CT1 -->|Encrypted Logs| S3
    CT2 -->|Encrypted Logs| S3
    S3 -.->|Uses| KMS
    CT1 -->|New Log File| SNS
    CT1 -->|Stream Events| CW
    
    style CT1 fill:#c8e6c9
    style CT2 fill:#c8e6c9
    style S3 fill:#e1f5fe
    style KMS fill:#fff3e0
    style SNS fill:#f3e5f5
    style CW fill:#e8f5e9

See: diagrams/03_domain2_cloudtrail_architecture.mmd

Diagram Explanation (Detailed):

The diagram shows a complete CloudTrail architecture across multiple regions. In Region 1 and Region 2, all API calls are captured by the CloudTrail service. Global services like IAM, STS, and CloudFront are recorded in a single region (typically us-east-1) to avoid duplication. CloudTrail aggregates events and delivers encrypted log files to a centralized S3 bucket every 5-15 minutes. The S3 bucket uses KMS encryption to protect log data at rest. When a new log file is delivered, CloudTrail can optionally send an SNS notification to trigger automated processing (like Lambda functions for real-time analysis). CloudTrail can also stream events directly to CloudWatch Logs for immediate querying and alerting. This architecture provides comprehensive audit logging with encryption, notifications, and real-time analysis capabilities.

Detailed Example 1: Investigating Unauthorized EC2 Launch

A security team receives an alert that an EC2 instance was launched in a production account outside normal business hours. Here's how they use CloudTrail to investigate: (1) They access the CloudTrail console and search for RunInstances events in the past 24 hours. (2) CloudTrail shows an event at 2:47 AM where an IAM user named "john.doe" launched a t3.large instance in us-west-2. (3) The event details reveal the source IP address was 203.0.113.45, which is not from the company's IP range. (4) They examine the request parameters and see the instance was launched with a security group allowing SSH from 0.0.0.0/0 (public internet). (5) Cross-referencing with IAM Access Advisor, they discover john.doe's credentials were compromised - the user hasn't logged in from the office in weeks. (6) They immediately disable the IAM user's access keys, terminate the unauthorized instance, and initiate the incident response process. CloudTrail provided the complete audit trail needed to identify the unauthorized action, determine the scope, and take corrective action.

Detailed Example 2: Compliance Audit for PCI DSS

A company needs to demonstrate compliance with PCI DSS requirements for their payment processing system. Here's how CloudTrail helps: (1) Auditors require proof that all access to cardholder data environments is logged and monitored. (2) The security team shows their CloudTrail configuration with a multi-region trail capturing all management events and data events for S3 buckets containing cardholder data. (3) They demonstrate log file integrity validation is enabled, proving logs haven't been tampered with. (4) CloudTrail logs are encrypted with KMS and stored in an S3 bucket with Object Lock enabled in compliance mode, preventing deletion for 7 years. (5) They show CloudWatch Logs integration with metric filters that alert on suspicious activities like failed authentication attempts or privilege escalation. (6) Using Athena, they query CloudTrail logs to generate reports showing who accessed cardholder data, when, and from where. (7) The auditors verify that CloudTrail provides the complete audit trail required by PCI DSS, including immutable logs, encryption, and long-term retention.

Detailed Example 3: Detecting Privilege Escalation

A security analyst wants to detect when IAM users attempt to escalate their privileges. Here's how they use CloudTrail: (1) They create a CloudWatch Logs metric filter that monitors CloudTrail events for specific IAM actions: iam:AttachUserPolicy, iam:AttachRolePolicy, iam:PutUserPolicy, iam:PutRolePolicy, and iam:CreateAccessKey. (2) The metric filter increments a counter whenever these actions occur. (3) They create a CloudWatch alarm that triggers when the counter exceeds 5 events in 5 minutes. (4) One day, the alarm fires. Investigating CloudTrail logs, they discover an IAM user "developer-1" attempted to attach the AdministratorAccess policy to their own user account. (5) The CloudTrail event shows the attempt failed due to insufficient permissions (the user lacked iam:AttachUserPolicy permission). (6) However, the attempt itself is suspicious. They review the user's recent activity and discover the account was compromised. (7) They disable the user's credentials and initiate incident response. CloudTrail's detailed logging enabled detection of the privilege escalation attempt before it succeeded.

Must Know (Critical Facts):

  • CloudTrail records API calls, not OS-level activity or application logs - it's for AWS API auditing only
  • Management events are recorded by default and free; data events (S3 object-level, Lambda invocations) require explicit configuration and incur charges
  • CloudTrail delivers log files to S3 every 5-15 minutes, not in real-time - use CloudWatch Logs integration for real-time analysis
  • Multi-region trails capture events from all regions in a single trail, simplifying management and reducing costs
  • Organization trails can capture events from all accounts in an AWS Organization, providing centralized logging
  • Log file integrity validation uses digest files to detect tampering - enable this for compliance requirements
  • CloudTrail Insights uses machine learning to detect unusual API activity patterns automatically

When to use (Comprehensive):

  • ✅ Use CloudTrail when: You need a complete audit trail of all API calls for security investigations, compliance, or operational troubleshooting
  • ✅ Use CloudTrail when: You must meet compliance requirements (PCI DSS, HIPAA, SOC 2) that mandate audit logging
  • ✅ Use CloudTrail when: You want to detect unauthorized access, privilege escalation, or suspicious API activity
  • ✅ Use CloudTrail when: You need to track changes to AWS resources and identify who made specific changes
  • ✅ Use CloudTrail when: You're implementing a multi-account strategy and need centralized logging across all accounts
  • ❌ Don't use CloudTrail when: You need real-time alerting (use CloudWatch Logs integration instead for near real-time)
  • ❌ Don't use CloudTrail when: You need to log OS-level activity or application logs (use CloudWatch Logs or third-party agents)
  • ❌ Don't use CloudTrail when: You only need to monitor specific resources (use service-specific logging like VPC Flow Logs or S3 access logs for better granularity)

Limitations & Constraints:

  • Delivery Delay: Log files are delivered every 5-15 minutes, not immediately - not suitable for real-time alerting without CloudWatch Logs integration
  • Data Event Costs: Logging S3 object-level or Lambda invocation events can be expensive at scale - use selectively
  • Log File Size: Each log file can contain up to 1,000 events - high-volume accounts generate many small files
  • Retention: CloudTrail itself doesn't enforce retention - you must configure S3 lifecycle policies
  • Query Performance: Querying CloudTrail logs in S3 directly is slow - use Athena or CloudWatch Logs Insights for analysis
  • Global Service Events: IAM, STS, and CloudFront events are only recorded in us-east-1 to avoid duplication

💡 Tips for Understanding:

  • Think of CloudTrail as "who did what, when, and from where" - it answers accountability questions
  • Remember: CloudTrail = API calls, CloudWatch Logs = application/system logs, VPC Flow Logs = network traffic
  • Multi-region trails are almost always the right choice - they simplify management and ensure complete coverage
  • Always enable log file integrity validation for production environments - it's free and proves logs weren't tampered with
  • Use CloudWatch Logs integration for real-time analysis, S3 for long-term storage and compliance

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Assuming CloudTrail logs everything including OS-level activity
    • Why it's wrong: CloudTrail only logs AWS API calls, not what happens inside EC2 instances or containers
    • Correct understanding: CloudTrail tracks AWS control plane operations; use CloudWatch Logs agent or third-party tools for OS/application logging
  • Mistake 2: Thinking CloudTrail provides real-time alerting
    • Why it's wrong: CloudTrail delivers log files every 5-15 minutes, creating a delay
    • Correct understanding: For real-time alerting, enable CloudWatch Logs integration or use EventBridge to capture events directly
  • Mistake 3: Not protecting the S3 bucket containing CloudTrail logs
    • Why it's wrong: If attackers gain access to the S3 bucket, they can delete logs to cover their tracks
    • Correct understanding: Use S3 bucket policies to restrict access, enable MFA Delete, use Object Lock for immutability, and enable versioning

🔗 Connections to Other Topics:

  • Relates to Security Hub because: CloudTrail findings are aggregated in Security Hub for centralized security monitoring
  • Builds on IAM by: Recording all IAM actions and providing audit trails for access management
  • Often used with Athena to: Query CloudTrail logs stored in S3 using SQL for security investigations
  • Integrates with CloudWatch Logs to: Enable real-time log analysis and alerting on suspicious API activity
  • Works with EventBridge to: Trigger automated responses to specific API calls (e.g., auto-remediation)

CloudTrail Event Types

Management Events vs Data Events:

CloudTrail categorizes events into two types based on the nature of the operation:

Management Events (Control Plane):

  • Operations that modify AWS resources: creating, deleting, or configuring resources
  • Examples: ec2:RunInstances, s3:CreateBucket, iam:CreateUser, rds:CreateDBInstance
  • Recorded by default in all trails at no additional cost
  • Essential for security auditing and compliance

Data Events (Data Plane):

  • Operations that access or modify data within resources
  • Examples: s3:GetObject, s3:PutObject, lambda:Invoke, dynamodb:GetItem
  • Must be explicitly enabled and incur additional charges
  • High volume - can generate millions of events in busy environments
  • Use selectively for sensitive data or compliance requirements

Read Events vs Write Events:

  • Read events: Operations that read data but don't modify it (s3:GetObject, dynamodb:GetItem)
  • Write events: Operations that create, modify, or delete data (s3:PutObject, ec2:RunInstances)
  • You can configure trails to log only write events to reduce volume and cost

Section 2: Amazon CloudWatch - Monitoring and Alerting

Introduction

The problem: AWS generates massive amounts of operational data - metrics, logs, and events. Without a centralized monitoring system, you cannot detect anomalies, troubleshoot issues, or respond to security events in real-time.

The solution: Amazon CloudWatch collects and tracks metrics, monitors log files, sets alarms, and automatically reacts to changes in your AWS resources. It provides real-time visibility into resource utilization, application performance, and operational health.

Why it's tested: CloudWatch is the primary monitoring service in AWS. The exam tests your ability to design monitoring solutions, create effective alarms, analyze logs, and troubleshoot monitoring issues.

Core Concepts

CloudWatch Metrics

What it is: CloudWatch Metrics are time-ordered data points that represent the behavior of your AWS resources and applications. AWS services automatically publish metrics (like EC2 CPU utilization), and you can publish custom metrics from your applications.

Why it exists: You cannot manage what you cannot measure. Metrics provide quantitative data about resource performance, enabling you to detect issues, optimize costs, and ensure applications meet performance requirements.

Real-world analogy: Metrics are like the gauges on a car dashboard - they show speed (throughput), fuel level (capacity), engine temperature (CPU), and warning lights (alarms). Just as you monitor these gauges while driving, you monitor CloudWatch metrics to ensure your AWS environment runs smoothly.

How it works (Detailed step-by-step):

  1. Metric Generation: AWS services automatically generate metrics (e.g., EC2 publishes CPUUtilization every 5 minutes by default, or every 1 minute with detailed monitoring enabled).
  2. Metric Publishing: Services publish metrics to CloudWatch using the PutMetricData API. Custom applications can also publish metrics.
  3. Metric Storage: CloudWatch stores metrics with different retention periods: 1-minute data points for 15 days, 5-minute data points for 63 days, 1-hour data points for 455 days.
  4. Metric Aggregation: CloudWatch aggregates metrics using statistics like Average, Sum, Minimum, Maximum, and SampleCount over specified periods.
  5. Metric Retrieval: You retrieve metrics using the GetMetricStatistics API or view them in the CloudWatch console with customizable graphs.
  6. Alarm Evaluation: CloudWatch alarms continuously evaluate metrics against thresholds and trigger actions when thresholds are breached.

📊 CloudWatch Monitoring Architecture Diagram:

graph TB
    subgraph "AWS Resources"
        EC2[EC2 Instances]
        RDS[RDS Databases]
        Lambda[Lambda Functions]
        ALB[Load Balancers]
    end
    
    subgraph "CloudWatch"
        Metrics[CloudWatch Metrics]
        Logs[CloudWatch Logs]
        Alarms[CloudWatch Alarms]
        Dashboards[CloudWatch Dashboards]
    end
    
    subgraph "Actions"
        SNS[SNS Notifications]
        ASG[Auto Scaling]
        Lambda2[Lambda Functions]
        Systems[Systems Manager]
    end
    
    EC2 -->|Metrics| Metrics
    RDS -->|Metrics| Metrics
    Lambda -->|Metrics| Metrics
    ALB -->|Metrics| Metrics
    
    EC2 -->|Logs| Logs
    Lambda -->|Logs| Logs
    
    Metrics --> Alarms
    Logs --> Alarms
    
    Alarms -->|Notify| SNS
    Alarms -->|Scale| ASG
    Alarms -->|Execute| Lambda2
    Alarms -->|Remediate| Systems
    
    Metrics --> Dashboards
    Logs --> Dashboards
    
    style Metrics fill:#c8e6c9
    style Logs fill:#e1f5fe
    style Alarms fill:#fff3e0
    style Dashboards fill:#f3e5f5

See: diagrams/03_domain2_cloudwatch_architecture.mmd

Diagram Explanation (Detailed):

The diagram illustrates CloudWatch's comprehensive monitoring architecture. AWS resources (EC2, RDS, Lambda, ALB) automatically publish metrics to CloudWatch Metrics and send logs to CloudWatch Logs. CloudWatch Metrics stores time-series data about resource performance, while CloudWatch Logs stores text-based log data from applications and services. CloudWatch Alarms continuously evaluate metrics and log patterns against defined thresholds. When thresholds are breached, alarms trigger actions: sending SNS notifications to administrators, triggering Auto Scaling to add capacity, invoking Lambda functions for custom remediation, or executing Systems Manager automation documents. CloudWatch Dashboards provide visual representations of metrics and logs, enabling real-time monitoring. This architecture enables proactive monitoring, automated responses, and comprehensive visibility across your AWS environment.

Detailed Example 1: Detecting Failed Login Attempts

A security team wants to detect brute-force attacks against their web application. Here's how they use CloudWatch: (1) Their application logs authentication events to CloudWatch Logs, including successful and failed login attempts. (2) They create a metric filter that searches for the pattern "Failed login attempt" in the log stream. (3) The metric filter increments a counter (FailedLoginCount) each time the pattern is found. (4) They create a CloudWatch alarm that triggers when FailedLoginCount exceeds 10 in a 5-minute period. (5) The alarm sends an SNS notification to the security team and triggers a Lambda function. (6) The Lambda function automatically blocks the source IP address by adding it to a WAF IP set. (7) One day, an attacker attempts to brute-force user accounts. After 10 failed attempts in 3 minutes, the alarm fires. (8) The security team receives an email notification, and the Lambda function blocks the attacker's IP address within seconds. The attack is stopped before any accounts are compromised. CloudWatch's metric filters and alarms enabled real-time detection and automated response.

Detailed Example 2: Monitoring EC2 CPU for Performance Issues

An operations team manages a fleet of EC2 instances running a critical application. Here's how they use CloudWatch metrics: (1) They enable detailed monitoring on all EC2 instances to get 1-minute metric granularity instead of the default 5-minute. (2) They create a CloudWatch alarm for each instance that triggers when CPUUtilization exceeds 80% for 3 consecutive periods (3 minutes). (3) The alarm sends an SNS notification to the operations team and triggers an Auto Scaling policy to add capacity. (4) They create a CloudWatch dashboard showing CPU utilization, network traffic, and disk I/O for all instances in a single view. (5) One day, CPU utilization on several instances spikes to 95%. The alarms fire within 3 minutes. (6) The operations team receives notifications and sees the spike on their dashboard. (7) Auto Scaling automatically launches additional instances to handle the load. (8) Investigating the logs, they discover a database query was causing high CPU usage. They optimize the query and CPU returns to normal. CloudWatch metrics provided early warning, automated scaling, and visibility needed to maintain application performance.

Detailed Example 3: Anomaly Detection for Security Events

A security analyst wants to detect unusual API activity that might indicate a compromised account. Here's how they use CloudWatch anomaly detection: (1) They enable CloudWatch anomaly detection on a custom metric that counts IAM API calls per hour. (2) CloudWatch uses machine learning to learn the normal pattern of IAM API calls over 2 weeks. (3) They create an alarm that triggers when the metric exceeds the expected range (anomaly band) by 2 standard deviations. (4) For weeks, IAM API activity follows a predictable pattern: high during business hours, low at night. (5) One Saturday at 3 AM, an attacker compromises an IAM user's credentials and begins enumerating permissions. (6) The IAM API call rate spikes to 500 calls per hour, far above the normal weekend rate of 10 calls per hour. (7) CloudWatch anomaly detection identifies this as an anomaly and triggers the alarm. (8) The security team investigates, discovers the compromised credentials, and disables the user. CloudWatch's machine learning-based anomaly detection caught the attack without requiring manual threshold tuning.

Must Know (Critical Facts):

  • CloudWatch Metrics have different retention periods: 1-minute data for 15 days, 5-minute for 63 days, 1-hour for 455 days
  • Detailed monitoring (1-minute metrics) costs extra but provides faster detection of issues
  • Custom metrics can have up to 10 dimensions, enabling fine-grained filtering and aggregation
  • CloudWatch alarms have three states: OK (metric within threshold), ALARM (metric breached threshold), INSUFFICIENT_DATA (not enough data to evaluate)
  • Composite alarms combine multiple alarms using AND/OR logic to reduce false positives
  • CloudWatch anomaly detection uses machine learning to automatically adjust thresholds based on metric patterns
  • Metric math allows you to perform calculations on metrics (e.g., calculate error rate from error count and request count)

CloudWatch Logs

What it is: CloudWatch Logs enables you to centralize logs from all your systems, applications, and AWS services in a single location. It stores log data indefinitely (or according to retention policies you set) and provides powerful querying capabilities.

Why it exists: Applications and systems generate logs containing valuable information about operations, errors, and security events. Without centralized log management, logs are scattered across many systems, making it difficult to troubleshoot issues, detect security threats, or analyze trends.

Real-world analogy: CloudWatch Logs is like a library that collects and organizes all books (logs) from different sources. Instead of searching through individual bookshelves (servers), you can search the entire library from one place.

How it works (Detailed step-by-step):

  1. Log Agent Installation: You install the CloudWatch Logs agent on EC2 instances or on-premises servers to collect log files.
  2. Log Stream Creation: The agent creates a log stream (a sequence of log events from a single source) within a log group (a collection of log streams with the same retention and permissions).
  3. Log Event Publishing: The agent reads log files and publishes log events to CloudWatch Logs using the PutLogEvents API.
  4. Log Storage: CloudWatch Logs stores log events with timestamps, enabling time-based queries and analysis.
  5. Log Retention: You configure retention policies (1 day to 10 years, or indefinitely) to control how long logs are stored.
  6. Log Querying: You use CloudWatch Logs Insights to query logs using a SQL-like query language, or create metric filters to extract metrics from log data.
  7. Log Export: You can export logs to S3 for long-term archival or analysis with other tools like Athena.

Detailed Example 1: Analyzing Application Errors

A development team needs to troubleshoot errors in their application. Here's how they use CloudWatch Logs: (1) Their application running on EC2 instances writes logs to /var/log/application.log. (2) They install the CloudWatch Logs agent and configure it to send application logs to a log group named /aws/application/production. (3) Each EC2 instance creates its own log stream within the log group. (4) When errors occur, developers use CloudWatch Logs Insights to query: fields @timestamp, @message | filter @message like /ERROR/ | sort @timestamp desc | limit 100. (5) This query returns the 100 most recent error messages. (6) They discover a pattern: all errors contain "Database connection timeout". (7) They investigate and find the RDS instance is experiencing high CPU, causing connection delays. (8) They scale up the RDS instance and errors stop. CloudWatch Logs enabled quick identification of the root cause by centralizing logs and providing powerful querying.

Detailed Example 2: Real-time Security Monitoring

A security team wants to detect when IAM policies are modified. Here's how they use CloudWatch Logs: (1) They configure CloudTrail to send events to CloudWatch Logs in real-time. (2) They create a metric filter that searches for IAM policy modification events: { ($.eventName = PutUserPolicy) || ($.eventName = PutRolePolicy) || ($.eventName = AttachUserPolicy) || ($.eventName = AttachRolePolicy) }. (3) The metric filter increments a counter (IAMPolicyChanges) each time a matching event is found. (4) They create a CloudWatch alarm that triggers when IAMPolicyChanges > 0 in a 1-minute period. (5) The alarm sends an SNS notification to the security team. (6) One day, a developer accidentally attaches the AdministratorAccess policy to a test user. (7) Within 60 seconds, the alarm fires and the security team receives a notification. (8) They review the CloudTrail event in CloudWatch Logs, see it was accidental, and ask the developer to remove the policy. CloudWatch Logs enabled real-time detection of a security-sensitive change.

Detailed Example 3: Compliance Reporting

A compliance team needs to prove that all SSH access to production servers is logged. Here's how they use CloudWatch Logs: (1) They configure the CloudWatch Logs agent on all EC2 instances to send /var/log/secure (which contains SSH login attempts) to CloudWatch Logs. (2) They create a log group /aws/ec2/production/secure with a 7-year retention policy to meet compliance requirements. (3) They use CloudWatch Logs Insights to generate a report of all successful SSH logins in the past month: fields @timestamp, user, sourceIP | filter @message like /Accepted publickey/ | stats count() by user. (4) The query shows which users logged in and how many times. (5) They export the results to CSV and provide it to auditors. (6) Auditors verify that all SSH access is logged and retained for the required period. CloudWatch Logs provided the centralized logging and retention needed for compliance.

Must Know (Critical Facts):

  • CloudWatch Logs stores log data indefinitely by default - you must set retention policies to control costs
  • Log groups are containers for log streams with shared retention, permissions, and encryption settings
  • Metric filters extract metrics from log data, enabling you to create alarms on log patterns
  • CloudWatch Logs Insights provides a query language for interactive log analysis - much faster than downloading logs
  • Subscription filters enable real-time processing of log data by streaming to Lambda, Kinesis, or Elasticsearch
  • CloudWatch Logs can be encrypted with KMS keys for data at rest
  • Cross-account log data sharing requires resource policies on the destination log group

When to use (Comprehensive):

  • ✅ Use CloudWatch Logs when: You need centralized logging for applications, systems, and AWS services
  • ✅ Use CloudWatch Logs when: You want to create alarms based on log patterns (e.g., error rates, security events)
  • ✅ Use CloudWatch Logs when: You need to query logs interactively for troubleshooting or analysis
  • ✅ Use CloudWatch Logs when: You want real-time log processing with Lambda or Kinesis
  • ✅ Use CloudWatch Logs when: You need to meet compliance requirements for log retention and encryption
  • ❌ Don't use CloudWatch Logs when: You need long-term log archival at low cost (export to S3 and use Glacier instead)
  • ❌ Don't use CloudWatch Logs when: You need complex log analysis or correlation (use Elasticsearch or third-party SIEM tools)
  • ❌ Don't use CloudWatch Logs when: Log volume is extremely high and cost is a concern (consider sampling or filtering)

Section 3: VPC Flow Logs - Network Traffic Monitoring

Introduction

The problem: Network traffic is invisible by default in AWS. Without visibility into network flows, you cannot detect network-based attacks, troubleshoot connectivity issues, or analyze traffic patterns.

The solution: VPC Flow Logs capture information about IP traffic going to and from network interfaces in your VPC. They record source/destination IP addresses, ports, protocols, packet counts, and accept/reject decisions.

Why it's tested: VPC Flow Logs are essential for network security monitoring. The exam tests your understanding of how to enable flow logs, analyze traffic patterns, detect security threats, and troubleshoot network issues.

Core Concepts

What are VPC Flow Logs

What it is: VPC Flow Logs are records of network traffic flowing through your VPC. Each flow log record represents a network flow (a sequence of packets between a source and destination) during a capture window (typically 10 minutes).

Why it exists: Network traffic contains critical security information: who is communicating with whom, which ports are being accessed, and whether traffic is being allowed or rejected. Flow logs provide this visibility, enabling security monitoring, forensics, and troubleshooting.

Real-world analogy: VPC Flow Logs are like security camera footage of a building's entrances and exits. They show who entered, who left, when, and whether they were allowed or denied entry. Just as security teams review footage to investigate incidents, you analyze flow logs to investigate network security events.

How it works (Detailed step-by-step):

  1. Flow Log Creation: You create a flow log for a VPC, subnet, or network interface, specifying the destination (CloudWatch Logs or S3).
  2. Traffic Capture: AWS captures metadata about network traffic at the network interface level, including source/destination IPs, ports, protocol, packet count, byte count, and action (ACCEPT or REJECT).
  3. Flow Aggregation: AWS aggregates packets into flows based on the 5-tuple (source IP, destination IP, source port, destination port, protocol) during a capture window (typically 10 minutes).
  4. Flow Record Creation: For each flow, AWS creates a flow log record containing all captured metadata.
  5. Log Delivery: AWS delivers flow log records to the specified destination (CloudWatch Logs or S3) every 10 minutes.
  6. Log Analysis: You analyze flow logs using CloudWatch Logs Insights, Athena (for S3), or third-party tools to detect threats, troubleshoot issues, or analyze traffic patterns.

📊 VPC Flow Logs Architecture Diagram:

graph TB
    subgraph "VPC"
        subgraph "Public Subnet"
            EC2_1[EC2 Instance]
            ENI_1[Network Interface]
        end
        subgraph "Private Subnet"
            EC2_2[EC2 Instance]
            ENI_2[Network Interface]
        end
        IGW[Internet Gateway]
        NAT[NAT Gateway]
    end
    
    Internet[Internet]
    
    FlowLogs[VPC Flow Logs Service]
    CWLogs[CloudWatch Logs]
    S3[S3 Bucket]
    Athena[Amazon Athena]
    
    Internet --> IGW
    IGW --> ENI_1
    ENI_1 --> EC2_1
    
    ENI_2 --> EC2_2
    ENI_2 --> NAT
    NAT --> IGW
    
    ENI_1 -.->|Traffic Metadata| FlowLogs
    ENI_2 -.->|Traffic Metadata| FlowLogs
    
    FlowLogs -->|Stream| CWLogs
    FlowLogs -->|Batch| S3
    
    S3 --> Athena
    
    style FlowLogs fill:#c8e6c9
    style CWLogs fill:#e1f5fe
    style S3 fill:#fff3e0
    style Athena fill:#f3e5f5

See: diagrams/03_domain2_vpc_flow_logs.mmd

Diagram Explanation (Detailed):

The diagram shows VPC Flow Logs capturing network traffic metadata from network interfaces in both public and private subnets. Traffic flows from the Internet through the Internet Gateway to EC2 instances in the public subnet, and from private subnet instances through the NAT Gateway. VPC Flow Logs Service captures metadata about all traffic at the network interface level, including source/destination IPs, ports, protocols, and accept/reject decisions. Flow logs can be delivered to CloudWatch Logs for real-time analysis and alerting, or to S3 for long-term storage and batch analysis. When stored in S3, you can query flow logs using Athena to investigate security incidents, analyze traffic patterns, or troubleshoot connectivity issues. This architecture provides comprehensive network visibility without impacting performance.

Detailed Example 1: Detecting Port Scanning

A security team wants to detect port scanning attacks against their infrastructure. Here's how they use VPC Flow Logs: (1) They enable VPC Flow Logs for their entire VPC, sending logs to S3. (2) They use Athena to query flow logs for rejected connections: SELECT sourceaddress, destinationport, COUNT(*) as attempts FROM vpc_flow_logs WHERE action = 'REJECT' GROUP BY sourceaddress, destinationport HAVING attempts > 100 ORDER BY attempts DESC. (3) The query identifies source IPs that attempted to connect to many different ports and were rejected. (4) One day, the query shows IP address 203.0.113.45 attempted connections to 500 different ports on their web server in 10 minutes, all rejected. (5) This is a clear port scan - the attacker is probing for open ports. (6) They add the IP address to their WAF IP block list and investigate whether any connections were successful. (7) Flow logs show all attempts were rejected by security groups, so no breach occurred. VPC Flow Logs enabled detection of the port scan and confirmation that defenses worked.

Detailed Example 2: Troubleshooting Connectivity Issues

An operations team is troubleshooting why an application cannot connect to a database. Here's how they use VPC Flow Logs: (1) They enable flow logs for the application server's network interface. (2) They attempt to connect to the database and observe the failure. (3) They query flow logs in CloudWatch Logs Insights: fields @timestamp, srcaddr, dstaddr, dstport, action | filter dstaddr = "10.0.2.50" and dstport = 3306 | sort @timestamp desc. (4) The query shows connection attempts to the database IP (10.0.2.50) on port 3306 (MySQL) with action = REJECT. (5) This means traffic is being blocked. They check security groups and discover the database security group doesn't allow inbound traffic from the application server's security group. (6) They update the security group rule to allow traffic and test again. (7) Flow logs now show action = ACCEPT and the application connects successfully. VPC Flow Logs pinpointed the exact cause of the connectivity issue.

Detailed Example 3: Analyzing Data Transfer Costs

A cost optimization team wants to understand data transfer patterns to reduce costs. Here's how they use VPC Flow Logs: (1) They enable flow logs for all VPCs, sending logs to S3. (2) They use Athena to analyze data transfer: SELECT srcaddr, dstaddr, SUM(bytes) as total_bytes FROM vpc_flow_logs WHERE dstaddr NOT LIKE '10.%' GROUP BY srcaddr, dstaddr ORDER BY total_bytes DESC LIMIT 100. (3) This query identifies the top 100 source/destination pairs by bytes transferred to external IPs (not internal 10.x.x.x addresses). (4) They discover one EC2 instance is transferring 500 GB per day to an external IP address. (5) Investigating, they find the instance is backing up data to an external service instead of using S3. (6) They reconfigure backups to use S3, eliminating data transfer charges. VPC Flow Logs provided visibility into data transfer patterns, enabling cost optimization.

Must Know (Critical Facts):

  • VPC Flow Logs capture metadata only, not packet contents - you cannot see the actual data being transferred
  • Flow logs can be created at VPC, subnet, or network interface level - subnet level is most common
  • Flow logs do not capture all traffic: DHCP, DNS to Amazon DNS, Windows license activation, instance metadata, and AWS Time Sync Service are excluded
  • Flow log records are delivered every 10 minutes, not in real-time - use for forensics and analysis, not real-time alerting
  • Custom flow log formats allow you to select which fields to capture, reducing storage costs
  • Flow logs can be sent to CloudWatch Logs (for real-time analysis) or S3 (for cost-effective long-term storage)
  • Rejected traffic (action = REJECT) indicates security group or NACL blocking - useful for detecting attacks

When to use (Comprehensive):

  • ✅ Use VPC Flow Logs when: You need visibility into network traffic for security monitoring or forensics
  • ✅ Use VPC Flow Logs when: You want to detect network-based attacks like port scanning or DDoS
  • ✅ Use VPC Flow Logs when: You need to troubleshoot connectivity issues between resources
  • ✅ Use VPC Flow Logs when: You want to analyze traffic patterns for cost optimization or capacity planning
  • ✅ Use VPC Flow Logs when: You must meet compliance requirements for network traffic logging
  • ❌ Don't use VPC Flow Logs when: You need to inspect packet contents (use Traffic Mirroring or third-party tools instead)
  • ❌ Don't use VPC Flow Logs when: You need real-time network monitoring (10-minute delay makes them unsuitable for real-time alerting)
  • ❌ Don't use VPC Flow Logs when: You only need to monitor specific applications (use application-level logging instead)

Section 4: AWS Config - Configuration Compliance

Introduction

The problem: AWS resources are constantly changing - instances are launched, security groups are modified, IAM policies are updated. Without tracking these changes, you cannot ensure resources remain compliant with security policies or troubleshoot configuration issues.

The solution: AWS Config continuously monitors and records AWS resource configurations and changes. It evaluates configurations against desired settings (Config Rules) and provides a complete history of configuration changes.

Why it's tested: Config is essential for compliance and governance. The exam tests your ability to design Config rules, troubleshoot configuration drift, and use Config for security auditing.

Core Concepts

What is AWS Config

What it is: AWS Config is a service that records the configuration of AWS resources in your account and tracks changes over time. It creates a configuration timeline showing how resources were configured at any point in time.

Why it exists: Compliance and security require knowing not just the current state of resources, but also how they changed over time. Config provides this visibility, enabling you to answer questions like "Who changed this security group?" or "Was this S3 bucket ever public?"

Real-world analogy: AWS Config is like a time-lapse camera that photographs your AWS environment every few minutes. You can review the photos to see how things changed, who made changes, and whether changes violated policies.

How it works (Detailed step-by-step):

  1. Config Recorder Setup: You enable AWS Config and specify which resource types to record (or record all supported resources).
  2. Configuration Snapshot: Config takes an initial snapshot of all resources, recording their current configuration.
  3. Change Detection: Config monitors resources for changes using CloudWatch Events and API calls.
  4. Configuration Item Creation: When a resource changes, Config creates a Configuration Item (CI) - a JSON document describing the resource's configuration at that point in time.
  5. Configuration History: Config stores CIs in an S3 bucket, creating a complete history of configuration changes.
  6. Rule Evaluation: Config Rules evaluate resource configurations against desired settings (e.g., "S3 buckets must not be public").
  7. Compliance Reporting: Config reports whether resources are compliant or non-compliant with rules, enabling automated remediation.

Detailed Example 1: Detecting Unauthorized Security Group Changes

A security team wants to ensure security groups never allow SSH from the internet. Here's how they use AWS Config: (1) They enable AWS Config to record security group configurations. (2) They create a Config Rule using the managed rule restricted-ssh that checks if security groups allow SSH (port 22) from 0.0.0.0/0. (3) All security groups are initially compliant. (4) One day, a developer accidentally adds a rule allowing SSH from 0.0.0.0/0 to a production security group. (5) Within minutes, Config evaluates the security group against the rule and marks it as non-compliant. (6) Config sends an SNS notification to the security team. (7) The security team reviews the Config timeline, sees who made the change and when, and contacts the developer. (8) They remove the rule and the security group returns to compliant status. AWS Config detected the policy violation and provided the audit trail needed to remediate it.

Detailed Example 2: Compliance Reporting for Auditors

A compliance team needs to prove all EBS volumes are encrypted. Here's how they use AWS Config: (1) They enable AWS Config to record EBS volume configurations. (2) They create a Config Rule using the managed rule encrypted-volumes that checks if EBS volumes are encrypted. (3) Config evaluates all existing and new EBS volumes against the rule. (4) The compliance dashboard shows 98% of volumes are compliant, but 5 volumes are non-compliant (unencrypted). (5) They investigate the non-compliant volumes and discover they're old test volumes. (6) They create encrypted snapshots, delete the old volumes, and restore from encrypted snapshots. (7) All volumes are now compliant. (8) They generate a Config compliance report showing 100% compliance and provide it to auditors. AWS Config provided continuous compliance monitoring and reporting.

Detailed Example 3: Investigating Configuration Drift

An operations team notices an application stopped working after a configuration change. Here's how they use AWS Config: (1) They access the Config timeline for the application's load balancer. (2) The timeline shows all configuration changes in chronological order. (3) They see that 2 hours ago, someone modified the load balancer's security group, removing a rule that allowed traffic from the application servers. (4) They review the CloudTrail event linked from the Config timeline and identify who made the change. (5) They restore the security group rule and the application starts working. (6) They implement a Config Rule to prevent removal of critical security group rules in the future. AWS Config's configuration timeline enabled quick identification of the change that caused the issue.

Must Know (Critical Facts):

  • AWS Config records resource configurations, not API calls - use CloudTrail for API auditing
  • Configuration Items (CIs) are point-in-time snapshots of resource configurations stored in S3
  • Config Rules evaluate resources against desired configurations - they don't prevent non-compliant changes, only detect them
  • Managed Config Rules are pre-built rules for common compliance checks (e.g., encrypted volumes, public S3 buckets)
  • Custom Config Rules use Lambda functions for complex compliance logic
  • Config Aggregators collect data from multiple accounts and regions into a single view
  • Remediation actions can automatically fix non-compliant resources using Systems Manager Automation documents

Section 5: Monitoring and Alerting Best Practices

Designing Effective Monitoring Solutions

Layered Monitoring Approach:

Effective security monitoring requires multiple layers working together:

  1. Infrastructure Layer: Monitor AWS resource health and performance (CloudWatch Metrics)
  2. Network Layer: Monitor network traffic patterns and anomalies (VPC Flow Logs)
  3. Application Layer: Monitor application logs and errors (CloudWatch Logs)
  4. API Layer: Monitor API calls and access patterns (CloudTrail)
  5. Configuration Layer: Monitor resource configuration compliance (AWS Config)
  6. Threat Detection Layer: Monitor for known threats and anomalies (GuardDuty, Security Hub)

Key Principles:

  • Comprehensive Coverage: Monitor all layers - gaps in monitoring create blind spots for attackers
  • Real-time Alerting: Use CloudWatch Logs integration with CloudTrail for near real-time security alerts
  • Automated Response: Trigger Lambda functions or Systems Manager automation for immediate remediation
  • Centralized Visibility: Aggregate logs and metrics in a central account for multi-account environments
  • Retention Policies: Balance compliance requirements with storage costs using appropriate retention periods

Common Monitoring Patterns

Pattern 1: Real-time Security Event Detection

  • CloudTrail → CloudWatch Logs → Metric Filter → CloudWatch Alarm → SNS/Lambda
  • Use for: Detecting IAM changes, unauthorized API calls, security group modifications
  • Latency: 1-2 minutes from event to alert

Pattern 2: Batch Log Analysis

  • CloudTrail/VPC Flow Logs → S3 → Athena queries
  • Use for: Forensic investigations, compliance reporting, trend analysis
  • Latency: 10-15 minutes for log delivery, then on-demand queries

Pattern 3: Anomaly Detection

  • CloudWatch Metrics → Anomaly Detection → CloudWatch Alarm
  • Use for: Detecting unusual API activity, traffic patterns, or resource utilization
  • Latency: Real-time evaluation with machine learning-based thresholds

Pattern 4: Compliance Monitoring

  • AWS Config → Config Rules → SNS notification → Automated remediation
  • Use for: Ensuring resources remain compliant with security policies
  • Latency: Minutes to hours depending on rule evaluation frequency

Troubleshooting Monitoring Issues

Common Issue 1: Missing CloudTrail Logs

  • Symptoms: Expected events not appearing in CloudTrail
  • Causes: Trail not enabled in the region, S3 bucket permissions incorrect, KMS key policy doesn't allow CloudTrail
  • Resolution: Verify trail status, check S3 bucket policy allows CloudTrail, ensure KMS key policy includes CloudTrail service

Common Issue 2: CloudWatch Alarms Not Triggering

  • Symptoms: Metric breaches threshold but alarm doesn't fire
  • Causes: Insufficient data points, alarm in INSUFFICIENT_DATA state, SNS topic permissions incorrect
  • Resolution: Check alarm history, verify metric is publishing data, confirm SNS topic policy allows CloudWatch

Common Issue 3: VPC Flow Logs Not Appearing

  • Symptoms: Flow logs enabled but no data in CloudWatch Logs or S3
  • Causes: IAM role permissions incorrect, S3 bucket policy doesn't allow flow logs, network interface has no traffic
  • Resolution: Verify IAM role has correct permissions, check S3 bucket policy, confirm traffic is flowing through the interface

Common Issue 4: Config Rules Showing Incorrect Compliance

  • Symptoms: Resources marked non-compliant when they should be compliant
  • Causes: Rule parameters incorrect, rule logic doesn't match intent, resource configuration not yet recorded
  • Resolution: Review rule parameters, test rule logic, trigger manual evaluation, check Config recorder status

Section 6: Log Analysis Techniques

CloudWatch Logs Insights Query Language

Basic Query Structure:

fields @timestamp, @message
| filter @message like /ERROR/
| sort @timestamp desc
| limit 100

Common Security Queries:

Query 1: Find Failed Authentication Attempts

fields @timestamp, userIdentity.principalId, sourceIPAddress, errorCode
| filter errorCode like /UnauthorizedOperation|AccessDenied/
| stats count() by userIdentity.principalId, sourceIPAddress
| sort count desc

Query 2: Detect Privilege Escalation Attempts

fields @timestamp, userIdentity.principalId, eventName
| filter eventName in ["AttachUserPolicy", "AttachRolePolicy", "PutUserPolicy", "PutRolePolicy"]
| sort @timestamp desc

Query 3: Identify High-Volume API Callers

fields @timestamp, userIdentity.principalId, eventName
| stats count() by userIdentity.principalId
| sort count desc
| limit 20

Athena Queries for CloudTrail Analysis

Query 1: Find All Actions by a Specific User

SELECT eventtime, eventname, sourceipaddress, requestparameters
FROM cloudtrail_logs
WHERE useridentity.principalid = 'AIDAI1234567890EXAMPLE'
ORDER BY eventtime DESC
LIMIT 100;

Query 2: Detect Console Logins from Unusual Locations

SELECT eventtime, useridentity.principalid, sourceipaddress, 
       requestparameters
FROM cloudtrail_logs
WHERE eventname = 'ConsoleLogin'
  AND sourceipaddress NOT LIKE '203.0.113.%'
ORDER BY eventtime DESC;

Query 3: Find All S3 Bucket Policy Changes

SELECT eventtime, useridentity.principalid, eventname, 
       requestparameters, responseelements
FROM cloudtrail_logs
WHERE eventname IN ('PutBucketPolicy', 'DeleteBucketPolicy', 
                    'PutBucketAcl')
ORDER BY eventtime DESC;

VPC Flow Logs Analysis with Athena

Query 1: Top Talkers (Most Active IPs)

SELECT sourceaddress, destinationaddress, 
       SUM(numbytes) as total_bytes,
       COUNT(*) as flow_count
FROM vpc_flow_logs
WHERE action = 'ACCEPT'
GROUP BY sourceaddress, destinationaddress
ORDER BY total_bytes DESC
LIMIT 100;

Query 2: Rejected Connections (Potential Attacks)

SELECT sourceaddress, destinationport, 
       COUNT(*) as attempts
FROM vpc_flow_logs
WHERE action = 'REJECT'
GROUP BY sourceaddress, destinationport
HAVING attempts > 100
ORDER BY attempts DESC;

Query 3: Data Exfiltration Detection

SELECT sourceaddress, destinationaddress,
       SUM(numbytes) as total_bytes
FROM vpc_flow_logs
WHERE destinationaddress NOT LIKE '10.%'
  AND destinationaddress NOT LIKE '172.16.%'
  AND destinationaddress NOT LIKE '192.168.%'
GROUP BY sourceaddress, destinationaddress
HAVING total_bytes > 10737418240  -- 10 GB
ORDER BY total_bytes DESC;

Section 4: Advanced Log Analysis and Threat Detection

Introduction

The problem: Collecting logs is only the first step. With millions of log entries generated daily, manually reviewing logs is impossible. You need automated analysis to detect security threats, identify anomalies, and investigate incidents quickly.

The solution: AWS provides multiple tools for log analysis including CloudWatch Logs Insights for real-time queries, Amazon Athena for SQL-based analysis of S3 logs, and GuardDuty for automated threat detection. Combined with custom metric filters and alarms, these enable proactive security monitoring.

Why it's tested: The exam tests your ability to design log analysis solutions, write queries to find security events, and identify patterns indicating threats. You must understand when to use each analysis tool and how to correlate events across multiple log sources.

Core Concepts

CloudWatch Logs Insights - Real-Time Log Queries

What it is: CloudWatch Logs Insights is a fully managed log analysis service that lets you interactively search and analyze log data in CloudWatch Logs using a purpose-built query language. It can scan millions of log events in seconds.

Why it exists: Traditional log analysis requires exporting logs to external tools or writing complex scripts. Logs Insights provides fast, interactive queries directly in CloudWatch without data movement. Essential for incident response and real-time investigation.

Real-world analogy: Logs Insights is like having a search engine for your logs. Just as Google lets you search billions of web pages instantly, Logs Insights lets you search millions of log entries in seconds with powerful filtering and aggregation.

How Logs Insights works (Detailed step-by-step):

  1. Query Specification: You write a query using the Logs Insights query language. Queries can filter, parse, aggregate, and visualize log data.

  2. Log Group Selection: Select which log groups to query. You can query multiple log groups simultaneously (e.g., all Lambda function logs).

  3. Time Range Selection: Specify the time range to search (last hour, last 24 hours, custom range). Narrower ranges return results faster.

  4. Query Execution: Logs Insights scans the specified log groups in parallel, applying filters and aggregations. It uses automatic field discovery to identify fields in your logs.

  5. Result Display: Results are displayed in a table or visualization (line chart, bar chart). You can sort, filter, and export results.

  6. Query Optimization: Logs Insights automatically optimizes queries by pushing filters down to the storage layer and using indexes where available.

Detailed Example 1: Finding Failed Login Attempts

A security team wants to identify failed SSH login attempts across all EC2 instances. They use CloudWatch Logs Insights to query auth logs:

Query:

fields @timestamp, @message
| filter @message like /Failed password/
| parse @message /Failed password for (?<user>\S+) from (?<ip>\S+)/
| stats count() by user, ip
| sort count desc

Query Explanation:

  • fields @timestamp, @message: Select timestamp and message fields
  • filter @message like /Failed password/: Only show logs containing "Failed password"
  • parse @message /.../ : Extract username and IP address using regex
  • stats count() by user, ip: Count failed attempts per user and IP
  • sort count desc: Show IPs with most failed attempts first

Results:

user        ip              count
root        203.0.113.45    127
admin       203.0.113.45    89
ubuntu      198.51.100.23   12

Analysis: IP 203.0.113.45 has 216 failed login attempts for root and admin accounts. This indicates a brute force attack. The security team blocks this IP in NACLs and creates a CloudWatch alarm to alert on future attempts.

Detailed Example 2: Detecting Data Exfiltration via S3

A company wants to detect large S3 downloads that might indicate data exfiltration. They query CloudTrail logs in CloudWatch:

Query:

fields @timestamp, userIdentity.principalId, requestParameters.bucketName, requestParameters.key, responseElements.contentLength
| filter eventName = "GetObject"
| filter responseElements.contentLength > 100000000
| stats sum(responseElements.contentLength) as totalBytes by userIdentity.principalId, requestParameters.bucketName
| sort totalBytes desc

Query Explanation:

  • Filter for GetObject events (S3 downloads)
  • Filter for downloads larger than 100MB
  • Sum total bytes downloaded per user and bucket
  • Sort by total bytes to find largest downloads

Results:

principalId                          bucketName          totalBytes
AIDAI23EXAMPLE                       customer-data       5368709120
AIDAI45EXAMPLE                       financial-records   2147483648

Analysis: User AIDAI23EXAMPLE downloaded 5GB from customer-data bucket. Investigation reveals this user's credentials were compromised. The security team rotates credentials, reviews access logs, and implements S3 access logging with Macie for sensitive data detection.

Detailed Example 3: Analyzing API Error Rates

A DevOps team wants to identify which API calls are failing most frequently to prioritize fixes:

Query:

fields @timestamp, eventName, errorCode, errorMessage
| filter ispresent(errorCode)
| stats count() as errorCount by eventName, errorCode
| sort errorCount desc
| limit 20

Query Explanation:

  • Filter for events with error codes (failed API calls)
  • Count errors by API call type and error code
  • Show top 20 most common errors

Results:

eventName           errorCode                   errorCount
AssumeRole          AccessDenied                1247
PutObject           NoSuchBucket                892
DescribeInstances   UnauthorizedOperation       456

Analysis: AssumeRole is failing with AccessDenied 1,247 times. This indicates a permissions issue with IAM roles. The team reviews role trust policies and identifies a misconfigured trust relationship.

Amazon Athena - SQL Analysis of S3 Logs

What it is: Amazon Athena is an interactive query service that lets you analyze data in S3 using standard SQL. It's serverless - you don't manage infrastructure, and you pay only for queries run.

Why it exists: CloudWatch Logs Insights is great for recent logs, but long-term log storage in CloudWatch is expensive. Most organizations store logs in S3 for cost-effective long-term retention. Athena enables SQL queries on S3 logs without loading data into a database.

Real-world analogy: Athena is like a librarian who can instantly find information in millions of archived documents without moving them. You ask questions in plain language (SQL), and Athena searches the archives (S3) and returns answers.

How Athena works (Detailed step-by-step):

  1. Table Definition: Create an Athena table that defines the schema of your logs (columns, data types). For CloudTrail, VPC Flow Logs, and ALB logs, AWS provides pre-built table definitions.

  2. Partition Configuration: Define partitions (e.g., by year/month/day) to improve query performance and reduce costs. Athena only scans partitions relevant to your query.

  3. Query Execution: Write SQL query and execute. Athena reads data directly from S3, applies filters and aggregations, and returns results.

  4. Result Storage: Query results are stored in an S3 bucket. You can download results or query them again.

  5. Cost Calculation: You pay $5 per TB of data scanned. Partitioning, compression, and columnar formats (Parquet) reduce costs by scanning less data.

Detailed Example 1: Analyzing CloudTrail Logs for Unauthorized Access

A security team wants to find all API calls made by a compromised IAM user over the past 6 months:

Step 1 - Create Athena Table:

CREATE EXTERNAL TABLE cloudtrail_logs (
    eventversion STRING,
    useridentity STRUCT<
        type:STRING,
        principalid:STRING,
        arn:STRING,
        accountid:STRING,
        invokedby:STRING,
        accesskeyid:STRING,
        userName:STRING>,
    eventtime STRING,
    eventsource STRING,
    eventname STRING,
    awsregion STRING,
    sourceipaddress STRING,
    useragent STRING,
    errorcode STRING,
    errormessage STRING,
    requestparameters STRING,
    responseelements STRING,
    additionaleventdata STRING,
    requestid STRING,
    eventid STRING,
    resources ARRAY<STRUCT<
        ARN:STRING,
        accountId:STRING,
        type:STRING>>,
    eventtype STRING,
    apiversion STRING,
    readonly STRING,
    recipientaccountid STRING,
    serviceeventdetails STRING,
    sharedeventid STRING,
    vpcendpointid STRING
)
PARTITIONED BY (region STRING, year STRING, month STRING, day STRING)
ROW FORMAT SERDE 'com.amazon.emr.hive.serde.CloudTrailSerde'
STORED AS INPUTFORMAT 'com.amazon.emr.cloudtrail.CloudTrailInputFormat'
OUTPUTFORMAT 'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION 's3://my-cloudtrail-bucket/AWSLogs/123456789012/CloudTrail/';

Step 2 - Query for Compromised User Activity:

SELECT 
    eventtime,
    eventname,
    eventsource,
    sourceipaddress,
    errorcode,
    requestparameters
FROM cloudtrail_logs
WHERE useridentity.username = 'compromised-user'
    AND year = '2024'
    AND month IN ('04', '05', '06', '07', '08', '09', '10')
ORDER BY eventtime DESC;

Results: Query returns 15,847 API calls made by the compromised user. Analysis reveals:

  • 12,000 calls from normal office IP (198.51.100.0)
  • 3,847 calls from suspicious IP in different country (203.0.113.0)
  • Suspicious calls include: CreateAccessKey, AttachUserPolicy, PutBucketPolicy
  • Attacker created new access keys and granted themselves admin permissions

Step 3 - Identify Affected Resources:

SELECT DISTINCT
    resources[0].arn as affected_resource,
    eventname,
    count(*) as action_count
FROM cloudtrail_logs
WHERE useridentity.username = 'compromised-user'
    AND sourceipaddress = '203.0.113.0'
    AND year = '2024'
    AND month >= '08'
GROUP BY resources[0].arn, eventname
ORDER BY action_count DESC;

Results: Attacker accessed 47 S3 buckets, modified 12 IAM policies, and created 5 new IAM users. The security team uses this information to assess impact and remediate.

Cost: Query scanned 2.3 TB of CloudTrail logs. Cost: $11.50 (2.3 TB × $5/TB). Much cheaper than loading 6 months of logs into a database.

Chapter Summary

What We Covered

  • CloudTrail: API activity logging for complete audit trails of all AWS actions
  • CloudWatch: Metrics, logs, and alarms for comprehensive monitoring and alerting
  • VPC Flow Logs: Network traffic monitoring for security analysis and troubleshooting
  • AWS Config: Configuration compliance monitoring and change tracking
  • Monitoring Best Practices: Layered monitoring, real-time alerting, automated response
  • Log Analysis: Query techniques for CloudWatch Logs Insights and Athena

Critical Takeaways

  1. CloudTrail is mandatory: Every AWS account should have CloudTrail enabled with multi-region trails, log file validation, and encryption
  2. Real-time matters: Use CloudWatch Logs integration with CloudTrail for near real-time security alerting (1-2 minutes vs 10-15 minutes for S3 delivery)
  3. Layer your monitoring: Combine CloudTrail (API), VPC Flow Logs (network), CloudWatch Logs (application), and Config (configuration) for complete visibility
  4. Automate responses: Use EventBridge, Lambda, and Systems Manager to automatically respond to security events
  5. Centralize logs: In multi-account environments, aggregate logs in a central security account for unified monitoring
  6. Protect your logs: Encrypt logs with KMS, use S3 Object Lock for immutability, restrict access with bucket policies
  7. Query efficiently: Use CloudWatch Logs Insights for real-time queries, Athena for historical analysis of S3-stored logs

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between CloudTrail management events and data events
  • I understand how to create CloudWatch metric filters and alarms for security events
  • I can analyze VPC Flow Logs to detect port scanning and data exfiltration
  • I know how to use AWS Config Rules to enforce security policies
  • I can write CloudWatch Logs Insights queries to find security events
  • I understand how to troubleshoot missing logs in CloudTrail, CloudWatch, and VPC Flow Logs
  • I can design a complete logging architecture for a multi-account environment

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-25 (Logging fundamentals)
  • Domain 2 Bundle 2: Questions 26-50 (Advanced monitoring and analysis)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections: CloudTrail event types, CloudWatch Logs metric filters, VPC Flow Logs analysis
  • Focus on: Troubleshooting missing logs, writing log queries, designing monitoring architectures

Quick Reference Card

Key Services:

  • CloudTrail: API call logging, audit trails, compliance
  • CloudWatch: Metrics, logs, alarms, dashboards
  • VPC Flow Logs: Network traffic metadata, security analysis
  • AWS Config: Configuration compliance, change tracking

Key Concepts:

  • Management Events: Control plane operations (creating/deleting resources)
  • Data Events: Data plane operations (reading/writing data)
  • Metric Filters: Extract metrics from log patterns
  • Flow Log Records: 5-tuple (src IP, dst IP, src port, dst port, protocol) + action

Decision Points:

  • Need API audit trail → CloudTrail
  • Need real-time alerting → CloudWatch Logs + Metric Filters + Alarms
  • Need network visibility → VPC Flow Logs
  • Need configuration compliance → AWS Config
  • Need long-term log storage → S3 with lifecycle policies
  • Need log analysis → CloudWatch Logs Insights (real-time) or Athena (historical)

Key Diagrams Created

  1. CloudTrail Architecture (diagrams/03_domain2_cloudtrail_architecture.mmd)

    • Multi-region trail setup with S3, KMS, SNS, and CloudWatch Logs integration
  2. CloudWatch Monitoring Architecture (diagrams/03_domain2_cloudwatch_architecture.mmd)

    • Metrics, logs, alarms, and automated actions
  3. VPC Flow Logs Architecture (diagrams/03_domain2_vpc_flow_logs.mmd)

    • Network traffic capture and analysis with CloudWatch Logs and Athena

Next Chapter: Chapter 3 - Infrastructure Security (20% of exam)


Section 4: Advanced Log Analysis and Threat Hunting

Introduction

The problem: Collecting logs is only the first step. Without effective analysis, logs are just data. Security teams need to identify patterns, detect anomalies, correlate events across services, and hunt for threats proactively. Manual log review is impractical at scale.

The solution: AWS provides multiple tools for log analysis: CloudWatch Logs Insights for real-time queries, Athena for historical analysis, CloudTrail Insights for anomaly detection, and Security Hub for aggregated findings. Together, these tools enable effective threat hunting and security analysis.

Why it's tested: The exam tests your ability to design log analysis solutions, write effective queries, identify security threats in logs, and correlate events across multiple log sources.

Core Concepts

CloudWatch Logs Insights - Real-Time Log Queries

What it is: CloudWatch Logs Insights is a fully managed log analysis service that enables you to interactively search and analyze log data in CloudWatch Logs. It uses a purpose-built query language optimized for log analysis.

Why it exists: Traditional log analysis requires exporting logs to external tools or writing complex scripts. CloudWatch Logs Insights provides fast, interactive queries directly on CloudWatch Logs without data movement.

Real-world analogy: CloudWatch Logs Insights is like a search engine for your logs. Just as Google lets you search the internet with simple queries, Logs Insights lets you search your logs with purpose-built queries.

How it works (Detailed step-by-step):

  1. Query Composition: You write a query using the CloudWatch Logs Insights query language.
  2. Log Group Selection: You select which log groups to query (can query multiple log groups simultaneously).
  3. Time Range: You specify the time range for the query (last hour, last day, custom range).
  4. Query Execution: CloudWatch Logs Insights executes the query across all log streams in the selected log groups.
  5. Result Aggregation: Results are aggregated and displayed in the console.
  6. Visualization: You can visualize results as line charts, bar charts, or stacked area charts.
  7. Query Saving: You can save frequently used queries for reuse.

📊 CloudWatch Logs Insights Queries Diagram:

graph TB
    subgraph "Log Sources"
        VPC[VPC Flow Logs]
        CT[CloudTrail Logs]
        App[Application Logs]
        Lambda[Lambda Logs]
    end
    
    subgraph "CloudWatch Logs"
        LG1[Log Group: VPC]
        LG2[Log Group: CloudTrail]
        LG3[Log Group: Application]
        LG4[Log Group: Lambda]
    end
    
    subgraph "CloudWatch Logs Insights"
        Query[Query Language<br/>fields, filter, stats, sort]
        Engine[Query Engine<br/>Parallel Execution]
        Results[Results<br/>Aggregated & Visualized]
    end
    
    subgraph "Use Cases"
        UC1[Find Failed Logins]
        UC2[Identify Top IPs]
        UC3[Detect Anomalies]
        UC4[Correlate Events]
    end
    
    VPC --> LG1
    CT --> LG2
    App --> LG3
    Lambda --> LG4
    
    LG1 --> Query
    LG2 --> Query
    LG3 --> Query
    LG4 --> Query
    
    Query --> Engine
    Engine --> Results
    
    Results --> UC1
    Results --> UC2
    Results --> UC3
    Results --> UC4
    
    style Query fill:#c8e6c9
    style Results fill:#e1f5fe

See: diagrams/03_domain2_cloudwatch_logs_insights_queries.mmd

Diagram Explanation (Detailed):

The diagram shows CloudWatch Logs Insights querying multiple log sources. VPC Flow Logs, CloudTrail logs, application logs, and Lambda logs are all sent to CloudWatch Logs in separate log groups. CloudWatch Logs Insights uses a purpose-built query language with commands like fields (select fields), filter (filter records), stats (aggregate data), and sort (order results). The query engine executes queries in parallel across all selected log groups and log streams. Results are aggregated and can be visualized as charts. Common use cases include: finding failed login attempts (filter CloudTrail logs for errorCode = "AccessDenied"), identifying top source IPs (stats count by sourceIPAddress), detecting anomalies (compare current metrics to historical baselines), and correlating events across services (join data from multiple log groups). CloudWatch Logs Insights enables fast, interactive log analysis without exporting data.

Detailed Example 1: Finding Failed Login Attempts

A security team wants to identify failed login attempts to investigate potential brute force attacks. Here's how they use CloudWatch Logs Insights: (1) They navigate to CloudWatch Logs Insights and select the CloudTrail log group. (2) They write a query to find failed authentication attempts:

fields @timestamp, userIdentity.principalId, sourceIPAddress, errorCode, errorMessage
| filter eventName = "ConsoleLogin" and errorCode = "Failed authentication"
| sort @timestamp desc
| limit 100

(3) They execute the query for the last 24 hours. (4) The results show 15 failed login attempts from IP address 203.0.113.45. (5) They investigate and discover it's a brute force attack. (6) They block the IP address using WAF. (7) They create a CloudWatch alarm to alert on multiple failed logins from the same IP. CloudWatch Logs Insights enabled rapid threat detection.

Detailed Example 2: Identifying Top API Callers

A security team wants to identify which IAM users are making the most API calls. Here's how they use CloudWatch Logs Insights: (1) They select the CloudTrail log group. (2) They write a query to aggregate API calls by user:

fields userIdentity.principalId
| stats count() as apiCalls by userIdentity.principalId
| sort apiCalls desc
| limit 10

(3) They execute the query for the last 7 days. (4) The results show the top 10 API callers. (5) They notice one IAM user has made 10x more API calls than others. (6) They investigate and discover the user's credentials were compromised and used for cryptocurrency mining. (7) They disable the user and rotate credentials. CloudWatch Logs Insights identified anomalous behavior.

Detailed Example 3: Detecting Unauthorized S3 Access

A security team wants to find unauthorized S3 access attempts. Here's how they use CloudWatch Logs Insights: (1) They select the CloudTrail log group. (2) They write a query to find denied S3 access:

fields @timestamp, userIdentity.principalId, requestParameters.bucketName, sourceIPAddress
| filter eventSource = "s3.amazonaws.com" and errorCode = "AccessDenied"
| stats count() as deniedAttempts by requestParameters.bucketName, sourceIPAddress
| sort deniedAttempts desc

(3) They execute the query for the last 30 days. (4) The results show 50 denied attempts to access a sensitive bucket from an external IP. (5) They investigate and discover a misconfigured application trying to access the wrong bucket. (6) They fix the application configuration. CloudWatch Logs Insights identified a configuration issue before it became a security incident.

Must Know (Critical Facts):

  • CloudWatch Logs Insights uses a purpose-built query language (not SQL)
  • Queries can span multiple log groups simultaneously
  • CloudWatch Logs Insights charges based on data scanned (GB)
  • Queries are executed in parallel for fast results
  • CloudWatch Logs Insights can visualize results as charts
  • Saved queries can be shared across teams
  • CloudWatch Logs Insights integrates with CloudWatch dashboards

When to use (Comprehensive):

  • ✅ Use when: You need real-time, interactive log analysis
  • ✅ Use when: You want to query CloudWatch Logs without exporting data
  • ✅ Use when: You need to correlate events across multiple log groups
  • ✅ Use when: You want to create visualizations from log data
  • ✅ Use when: You need ad-hoc queries for security investigations
  • ❌ Don't use when: You need to query historical logs in S3 (use Athena instead)
  • ❌ Don't use when: You need complex joins or SQL features (use Athena instead)

Amazon Athena - SQL Queries on S3 Logs

What it is: Amazon Athena is an interactive query service that enables you to analyze data in S3 using standard SQL. For security, Athena is commonly used to query CloudTrail logs, VPC Flow Logs, and other logs stored in S3.

Why it exists: CloudWatch Logs Insights is great for real-time analysis, but logs are often archived to S3 for long-term retention. Athena enables SQL queries on these archived logs without loading them into a database.

Real-world analogy: Athena is like a librarian who can search through archived documents in a warehouse. You don't need to bring all documents to your desk - the librarian searches them where they are and brings you the results.

How it works (Detailed step-by-step):

  1. Table Definition: You create an Athena table defining the schema of your log data in S3.
  2. Partition Configuration: You configure partitions (e.g., by date) to improve query performance and reduce costs.
  3. SQL Query: You write a standard SQL query to analyze the log data.
  4. Query Execution: Athena executes the query directly on S3 data without loading it into a database.
  5. Result Delivery: Query results are returned and can be saved to S3.
  6. Cost: You pay only for the data scanned by queries (compressed and partitioned data reduces costs).

📊 Athena Query Flow Diagram:

graph TB
    subgraph "S3 Buckets"
        S3_CT[CloudTrail Logs<br/>s3://logs/cloudtrail/]
        S3_VPC[VPC Flow Logs<br/>s3://logs/vpcflow/]
        S3_ALB[ALB Access Logs<br/>s3://logs/alb/]
    end
    
    subgraph "Athena"
        Table1[Table: cloudtrail_logs<br/>Partitioned by date]
        Table2[Table: vpc_flow_logs<br/>Partitioned by date]
        Table3[Table: alb_logs<br/>Partitioned by date]
        
        Query[SQL Query<br/>SELECT * FROM cloudtrail_logs<br/>WHERE eventName = 'DeleteBucket'<br/>AND date >= '2024-01-01']
        
        Engine[Query Engine<br/>Presto-based]
    end
    
    Results[Query Results<br/>Saved to S3]
    
    S3_CT -.->|Schema| Table1
    S3_VPC -.->|Schema| Table2
    S3_ALB -.->|Schema| Table3
    
    Table1 --> Query
    Query --> Engine
    Engine -->|Scan S3 Data| S3_CT
    Engine --> Results
    
    style Query fill:#c8e6c9
    style Results fill:#e1f5fe
    style Engine fill:#fff3e0

See: diagrams/03_domain2_athena_query_flow.mmd

Diagram Explanation (Detailed):

The diagram shows Athena querying logs stored in S3. Three S3 buckets contain different log types: CloudTrail logs, VPC Flow Logs, and ALB access logs. Athena tables are created defining the schema for each log type. Tables are partitioned by date to improve query performance and reduce costs (queries only scan relevant partitions). A SQL query is written to find all DeleteBucket events in CloudTrail logs since January 1, 2024. The Athena query engine (based on Presto) executes the query by scanning only the relevant S3 data (partitions for dates >= 2024-01-01). Query results are returned and can be saved to S3 for further analysis. Athena enables SQL queries on archived logs without loading them into a database, making it cost-effective for historical log analysis.

Detailed Example 1: Investigating Suspicious API Activity

A security team receives an alert about suspicious API activity. Here's how they use Athena: (1) They have CloudTrail logs stored in S3 with an Athena table configured. (2) They write a SQL query to find all API calls from a suspicious IP address:

SELECT eventtime, eventsource, eventname, useridentity.principalid, sourceipaddress
FROM cloudtrail_logs
WHERE sourceipaddress = '203.0.113.45'
  AND date >= '2024-01-01'
ORDER BY eventtime DESC
LIMIT 100;

(3) They execute the query, which scans only the relevant date partitions. (4) The results show the IP made 500 API calls in 1 hour, including CreateUser, AttachUserPolicy, and CreateAccessKey. (5) They identify this as a privilege escalation attack. (6) They disable the compromised credentials and investigate how the attacker gained access. Athena enabled rapid investigation of historical logs.

Detailed Example 2: Analyzing VPC Flow Logs for Network Threats

A security team wants to identify potential data exfiltration. Here's how they use Athena: (1) They have VPC Flow Logs stored in S3 with an Athena table configured. (2) They write a SQL query to find large data transfers to external IPs:

SELECT sourceaddr, dstaddr, SUM(bytes) as total_bytes
FROM vpc_flow_logs
WHERE action = 'ACCEPT'
  AND dstaddr NOT LIKE '10.%'
  AND date >= '2024-01-01'
GROUP BY sourceaddr, dstaddr
HAVING SUM(bytes) > 10000000000
ORDER BY total_bytes DESC;

(3) They execute the query to find connections transferring more than 10GB to external IPs. (4) The results show an EC2 instance transferred 50GB to an unknown external IP. (5) They investigate and discover the instance was compromised and used for data exfiltration. (6) They isolate the instance and perform forensic analysis. Athena identified potential data exfiltration from VPC Flow Logs.

Detailed Example 3: Compliance Reporting with Athena

A company needs to generate a compliance report showing all IAM policy changes. Here's how they use Athena: (1) They write a SQL query to find all IAM policy modifications:

SELECT eventtime, useridentity.principalid, eventname, 
       requestparameters.policyname, requestparameters.policyarn
FROM cloudtrail_logs
WHERE eventsource = 'iam.amazonaws.com'
  AND eventname IN ('CreatePolicy', 'DeletePolicy', 'CreatePolicyVersion', 
                     'AttachUserPolicy', 'AttachRolePolicy', 'AttachGroupPolicy')
  AND date >= '2024-01-01' AND date <= '2024-12-31'
ORDER BY eventtime;

(2) They execute the query for the entire year. (3) The results show all IAM policy changes with timestamps and principals. (4) They export the results to CSV for the compliance report. (5) The auditor reviews the report and confirms compliance. Athena enabled efficient compliance reporting from historical logs.

Must Know (Critical Facts):

  • Athena uses standard SQL (Presto-based) for queries
  • Athena charges based on data scanned (compressed and partitioned data reduces costs)
  • Athena tables are schema-on-read (data stays in S3, schema is applied during queries)
  • Partitioning by date significantly improves query performance and reduces costs
  • Athena can query data in multiple formats: JSON, Parquet, ORC, CSV
  • Athena integrates with QuickSight for visualization
  • Athena results can be saved to S3 for further analysis

When to use (Comprehensive):

  • ✅ Use when: You need to query historical logs stored in S3
  • ✅ Use when: You want to use SQL for log analysis
  • ✅ Use when: You need to generate compliance reports from logs
  • ✅ Use when: You want to analyze large volumes of log data cost-effectively
  • ✅ Use when: You need to join data from multiple log sources
  • ❌ Don't use when: You need real-time log analysis (use CloudWatch Logs Insights instead)
  • ❌ Don't use when: Logs are only in CloudWatch Logs and not archived to S3

CloudTrail Insights - Automated Anomaly Detection

What it is: CloudTrail Insights automatically analyzes CloudTrail management events to detect unusual API activity. It uses machine learning to establish a baseline of normal activity and alerts on anomalies.

Why it exists: Manually reviewing CloudTrail logs for anomalies is impractical. CloudTrail Insights automates anomaly detection, identifying unusual patterns that may indicate security issues or operational problems.

Real-world analogy: CloudTrail Insights is like a security analyst who learns your normal patterns and alerts you when something unusual happens. If you normally make 10 API calls per hour but suddenly make 1,000, Insights alerts you.

How it works (Detailed step-by-step):

  1. Baseline Learning: CloudTrail Insights analyzes your API activity over time to establish a baseline of normal behavior.
  2. Continuous Monitoring: Insights continuously monitors API activity for deviations from the baseline.
  3. Anomaly Detection: When API activity significantly exceeds the baseline, Insights generates an Insights event.
  4. Event Details: The Insights event includes details about the anomaly: which API, how much it exceeded the baseline, and the time period.
  5. Integration: Insights events are delivered to CloudTrail, S3, and optionally EventBridge for automated response.

📊 CloudTrail Insights Diagram:

graph TB
    subgraph "Normal Activity"
        Normal[Baseline: 10 API calls/hour<br/>Learned over 7 days]
    end
    
    subgraph "Anomalous Activity"
        Anomaly[Spike: 1,000 API calls/hour<br/>100x baseline]
    end
    
    subgraph "CloudTrail Insights"
        Baseline[Baseline Learning<br/>Machine Learning]
        Detection[Anomaly Detection<br/>Statistical Analysis]
        Event[Insights Event<br/>Details + Context]
    end
    
    subgraph "Response"
        CT[CloudTrail Console<br/>View Insights]
        EB[EventBridge<br/>Automated Response]
        SNS[SNS Notification<br/>Alert Security Team]
    end
    
    Normal --> Baseline
    Baseline --> Detection
    Anomaly --> Detection
    Detection --> Event
    
    Event --> CT
    Event --> EB
    EB --> SNS
    
    style Anomaly fill:#ffebee
    style Event fill:#fff3e0
    style SNS fill:#c8e6c9

See: diagrams/03_domain2_cloudtrail_insights.mmd

Diagram Explanation (Detailed):

The diagram shows CloudTrail Insights detecting anomalous API activity. CloudTrail Insights learns a baseline of normal activity over 7 days: typically 10 API calls per hour. It continuously monitors API activity using statistical analysis. When API activity spikes to 1,000 calls per hour (100x the baseline), Insights detects the anomaly. An Insights event is generated with details: which API calls spiked, the magnitude of the spike, and the time period. The Insights event is visible in the CloudTrail console for investigation. The event is also sent to EventBridge, enabling automated responses like sending SNS notifications to alert the security team. CloudTrail Insights automates anomaly detection, identifying unusual activity that may indicate security issues like compromised credentials or misconfigurations.

Detailed Example 1: Detecting Compromised Credentials

A company's IAM user credentials are compromised. Here's how CloudTrail Insights helps: (1) CloudTrail Insights has learned the user normally makes 5 API calls per hour. (2) The attacker uses the compromised credentials to make 500 API calls per hour (100x baseline). (3) CloudTrail Insights detects the anomaly and generates an Insights event. (4) The Insights event is sent to EventBridge. (5) An EventBridge rule triggers a Lambda function that disables the user's access keys. (6) An SNS notification alerts the security team. (7) The security team investigates and confirms the credentials were compromised. (8) They rotate credentials and investigate how the compromise occurred. CloudTrail Insights detected the compromise within minutes.

Detailed Example 2: Identifying Misconfigured Automation

A company deploys a new automation script. Here's how CloudTrail Insights helps: (1) The script has a bug causing it to make 10,000 DescribeInstances API calls per minute. (2) CloudTrail Insights detects the anomaly (normal baseline is 10 calls per minute). (3) An Insights event is generated and sent to EventBridge. (4) The security team receives an alert. (5) They investigate and discover the buggy script. (6) They stop the script and fix the bug. CloudTrail Insights identified the misconfiguration before it caused significant costs or rate limiting.

Must Know (Critical Facts):

  • CloudTrail Insights analyzes management events only (not data events)
  • Insights uses machine learning to establish baselines (typically 7 days of data)
  • Insights detects write API anomalies (not read APIs)
  • Insights events are delivered to CloudTrail, S3, and EventBridge
  • Insights has additional costs beyond standard CloudTrail
  • Insights is enabled per trail (not account-wide)

When to use (Comprehensive):

  • ✅ Use when: You want automated anomaly detection for API activity
  • ✅ Use when: You need to detect compromised credentials quickly
  • ✅ Use when: You want to identify misconfigurations or runaway automation
  • ✅ Use when: You need to detect unusual administrative activity
  • ❌ Don't use when: You only care about specific known threats (use CloudWatch alarms instead)
  • ❌ Don't use when: You need to detect data event anomalies (Insights only analyzes management events)

Chapter Summary

What We Covered

This chapter covered Domain 2: Security Logging and Monitoring (18% of exam), including:

  • Monitoring and Alerting: CloudWatch, EventBridge, metric filters, alarms, automated audits
  • Troubleshooting: Service configuration, permissions, custom application metrics
  • Logging Solutions: CloudTrail, VPC Flow Logs, CloudWatch Logs, log storage, lifecycle management
  • Log Analysis: Athena, CloudWatch Logs Insights, CloudTrail Insights, pattern identification
  • Centralized Logging: Multi-account strategies, log aggregation, cross-region replication

Critical Takeaways

  1. CloudTrail: Logs all API calls, essential for auditing and compliance, enable organization trail
  2. VPC Flow Logs: Network traffic monitoring, troubleshooting connectivity, security analysis
  3. CloudWatch: Metrics, logs, alarms, dashboards, anomaly detection
  4. Athena: Query logs in S3 using SQL, partition for performance, use for threat hunting
  5. CloudWatch Logs Insights: Real-time log analysis, query language, pattern detection
  6. CloudTrail Insights: Automated anomaly detection for API activity, ML-based
  7. Log Lifecycle: S3 Lifecycle policies, Glacier archival, retention compliance

Self-Assessment Checklist

Test yourself before moving on:

  • I can design a comprehensive logging strategy for AWS accounts
  • I understand the difference between CloudTrail, VPC Flow Logs, and CloudWatch Logs
  • I know how to troubleshoot missing logs and permissions issues
  • I can write Athena queries to analyze CloudTrail logs
  • I understand CloudWatch Logs Insights query syntax
  • I know how to set up metric filters and alarms
  • I can design log retention and lifecycle policies
  • I understand CloudTrail Insights and when to use it
  • I know how to centralize logs across multiple accounts
  • I can troubleshoot logging configuration issues

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-25 (Logging focus)
  • Domain 2 Bundle 2: Questions 26-50 (Monitoring focus)
  • Logging & Monitoring Services Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: Athena queries, CloudWatch Logs Insights, log lifecycle management
  • Focus on: Query syntax, troubleshooting, centralized logging architectures

Quick Reference Card

Key Services:

  • CloudTrail: API call logging, audit trail, compliance
  • VPC Flow Logs: Network traffic logs, security analysis
  • CloudWatch Logs: Application logs, centralized logging
  • CloudWatch Metrics: Performance monitoring, alarms
  • Athena: SQL queries on S3 logs
  • CloudWatch Logs Insights: Real-time log analysis

Decision Points:

  • Need API audit trail? → CloudTrail
  • Need network traffic logs? → VPC Flow Logs
  • Need application logs? → CloudWatch Logs
  • Need to query logs? → Athena (S3) or Logs Insights (CloudWatch)
  • Need anomaly detection? → CloudTrail Insights or CloudWatch Anomaly Detection
  • Need real-time alerting? → CloudWatch Alarms + EventBridge

Logging Best Practices:

  1. Enable CloudTrail organization trail
  2. Enable VPC Flow Logs on all VPCs
  3. Centralize logs in dedicated security account
  4. Encrypt logs with KMS
  5. Enable log file validation
  6. Set appropriate retention periods
  7. Use S3 Lifecycle for cost optimization
  8. Enable CloudTrail Insights for anomaly detection

Chapter 2 Complete

Next Chapter: 04_domain3_infrastructure - Infrastructure Security (20% of exam)


Chapter Summary

What We Covered

This chapter explored Security Logging and Monitoring, the foundation of AWS security operations:

Monitoring and Alerting Design: Analyzing architectures for monitoring requirements, designing environment and workload monitoring with CloudWatch and EventBridge, setting up automated audits with Security Hub custom insights, and defining metrics and thresholds for security alerting.

Troubleshooting Monitoring: Analyzing service configuration and permissions when monitoring fails, troubleshooting custom application reporting issues, and evaluating logging and monitoring alignment with security requirements.

Logging Solution Design: Configuring logging for AWS services (CloudTrail, VPC Flow Logs, CloudWatch Logs, Route 53 query logs, S3 access logs, ELB logs, WAF logs), identifying logging requirements and sources, and implementing log storage and lifecycle management.

Logging Troubleshooting: Identifying misconfiguration and missing permissions that prevent logging, determining the cause of missing logs, and ensuring log delivery and integrity.

Log Analysis: Using Athena and CloudWatch Logs filter for log analysis, leveraging CloudWatch Logs Insights, CloudTrail Insights, and Security Hub insights, and identifying patterns and anomalies in logs.

Critical Takeaways

  1. Logging is Non-Negotiable: Without comprehensive logging, you cannot detect threats, investigate incidents, or prove compliance. Enable CloudTrail, VPC Flow Logs, and service-specific logs for all critical resources.

  2. Centralize Everything: Use centralized logging architectures with dedicated S3 buckets, CloudWatch Logs aggregation, and Security Hub for findings. Multi-account environments require organization trails and log aggregators.

  3. Automate Alerting: Manual log review doesn't scale. Use CloudWatch metric filters, alarms, and EventBridge rules to automatically detect and alert on security events.

  4. Retention Matters: Balance cost with compliance requirements. Use S3 lifecycle policies to transition logs to Glacier for long-term retention, and CloudWatch Logs retention policies for operational logs.

  5. Immutability for Forensics: Use S3 Object Lock and Glacier Vault Lock to make logs immutable for forensic investigations and compliance. Attackers often try to delete logs to cover their tracks.

  6. Query Performance: Partition Athena tables by date for efficient queries. Use CloudWatch Logs Insights for real-time analysis. Know when to use each tool.

  7. Permissions are Critical: Most logging failures are due to missing IAM permissions or incorrect S3 bucket policies. CloudTrail needs write access to S3, VPC Flow Logs need CloudWatch Logs permissions, etc.

  8. Monitor the Monitors: Set up alarms for logging failures (CloudTrail stopped, VPC Flow Logs delivery failures). Use CloudWatch Logs metric filters to detect gaps in log delivery.

Self-Assessment Checklist

Test yourself before moving on:

  • I can design a comprehensive monitoring strategy for AWS architectures
  • I understand how to use CloudWatch, EventBridge, and SNS for alerting
  • I can set up automated audits using Security Hub custom insights
  • I know how to define appropriate metrics and thresholds for security events
  • I can troubleshoot missing CloudWatch logs and metrics
  • I understand how to diagnose EventBridge rule failures
  • I can configure CloudTrail for single-account and multi-account environments
  • I know how to enable and configure VPC Flow Logs, Route 53 query logs, S3 access logs, ELB logs, and WAF logs
  • I can design log aggregation strategies for multi-account environments
  • I understand log storage options and lifecycle management (S3, Glacier, CloudWatch Logs retention)
  • I can troubleshoot logging permission issues (IAM roles, S3 bucket policies, KMS encryption)
  • I know how to determine the cause of missing logs
  • I can write Athena queries to analyze CloudTrail and VPC Flow Logs
  • I understand how to use CloudWatch Logs Insights for log analysis
  • I can identify patterns and anomalies in logs using CloudTrail Insights and Security Hub insights

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-25 (Monitoring, Alerting, and Logging Design)
  • Domain 2 Bundle 2: Questions 26-50 (Troubleshooting and Log Analysis)
  • Logging & Monitoring Services Bundle: All 50 questions (Service-specific scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review CloudTrail configuration for organization trails and multi-region trails
  • Practice writing Athena queries with proper partitioning
  • Study VPC Flow Logs format and analysis techniques
  • Focus on troubleshooting permission issues for logging services

Quick Reference Card

Key Services:

  • CloudTrail: API call logging, management events, data events, Insights for anomaly detection
  • CloudWatch: Metrics, logs, alarms, dashboards, Logs Insights for queries
  • VPC Flow Logs: Network traffic logging (accepted/rejected connections)
  • EventBridge: Event-driven automation and alerting
  • Athena: SQL queries on S3 data (CloudTrail, VPC Flow Logs, etc.)

Key Concepts:

  • Organization Trail: CloudTrail trail that logs events for all accounts in an AWS Organization
  • Metric Filter: CloudWatch Logs filter that extracts metrics from log data
  • Log Aggregation: Centralizing logs from multiple accounts/regions into a single location
  • Log Immutability: Using S3 Object Lock or Glacier Vault Lock to prevent log deletion/modification

Logging Checklist:

  • ✅ CloudTrail enabled in all regions with management and data events
  • ✅ VPC Flow Logs enabled for all VPCs (capture accepted and rejected traffic)
  • ✅ S3 access logging enabled for sensitive buckets
  • ✅ ELB access logs enabled for all load balancers
  • ✅ Route 53 query logging enabled for DNS monitoring
  • ✅ WAF logging enabled for web application firewall analysis
  • ✅ CloudWatch Logs retention policies configured
  • ✅ S3 lifecycle policies for log archival to Glacier
  • ✅ S3 Object Lock enabled for forensic log buckets

Decision Points:

  • Real-time analysis → CloudWatch Logs Insights
  • Historical analysis → Athena with partitioned tables
  • Anomaly detection → CloudTrail Insights, CloudWatch anomaly detection
  • Cross-service correlation → Security Hub insights, Detective
  • Long-term retention → S3 with lifecycle policies to Glacier
  • Immutable logs → S3 Object Lock (compliance mode) or Glacier Vault Lock

Exam Tips:

  • Know the difference between CloudWatch Logs Insights (real-time, CloudWatch data) and Athena (historical, S3 data)
  • Understand CloudTrail event types: management events (control plane), data events (data plane), Insights events (anomalies)
  • Remember that VPC Flow Logs don't capture packet contents, only metadata (source, destination, ports, protocol, action)
  • Multi-account logging requires organization trails or log aggregation with cross-account S3 bucket policies
  • Most logging failures are permission issues: check IAM roles, S3 bucket policies, and KMS key policies


Chapter Summary

What We Covered

This chapter explored AWS security logging and monitoring capabilities across five critical areas:

Monitoring and Alerting Design

  • Analyzing architectures to identify monitoring requirements and data sources
  • Designing environment and workload monitoring based on business requirements
  • Setting up automated audits using Security Hub custom insights
  • Defining metrics and thresholds that generate meaningful alerts

Troubleshooting Monitoring and Alerting

  • Analyzing service configuration and permissions for monitoring failures
  • Troubleshooting custom application reporting issues
  • Evaluating logging and monitoring alignment with security requirements
  • Identifying and resolving gaps in monitoring coverage

Logging Solution Design and Implementation

  • Configuring logging for AWS services (CloudTrail, VPC Flow Logs, CloudWatch Logs)
  • Identifying logging requirements and sources for comprehensive coverage
  • Implementing log storage and lifecycle management
  • Centralizing logs across multi-account environments

Logging Solution Troubleshooting

  • Identifying misconfiguration and permission issues preventing log delivery
  • Determining causes of missing or incomplete logs
  • Resolving KMS encryption issues with logging
  • Validating log integrity and completeness

Log Analysis Solution Design

  • Using Athena and CloudWatch Logs filters for log analysis
  • Leveraging CloudWatch Logs Insights, CloudTrail Insights, and Security Hub insights
  • Identifying patterns and anomalies in logs
  • Normalizing, parsing, and correlating logs from multiple sources

Critical Takeaways

  1. CloudTrail is mandatory: Enable organization trail with log file validation and encryption for complete API activity tracking
  2. VPC Flow Logs capture network traffic: Enable VPC Flow Logs at VPC level with custom format to capture all network communications
  3. CloudWatch Logs centralizes application logs: Use CloudWatch Logs for application logging with appropriate retention periods
  4. Athena queries logs at scale: Use Athena with partitioned tables to query CloudTrail and VPC Flow Logs efficiently
  5. Metric filters detect anomalies: Create CloudWatch metric filters to detect security events and trigger alarms
  6. Security Hub custom insights: Create custom insights in Security Hub to track specific security metrics and trends
  7. Log lifecycle management: Implement S3 lifecycle policies to transition logs to Glacier and eventually delete based on retention requirements
  8. Centralized logging architecture: Use organization trail and log aggregation to centralize logs from all accounts
  9. Log immutability: Enable S3 Object Lock in compliance mode to ensure logs cannot be modified or deleted
  10. Real-time log processing: Use CloudWatch Logs subscription filters with Kinesis for real-time log analysis and alerting

Self-Assessment Checklist

Test yourself before moving on:

Monitoring and Alerting:

  • I can analyze an architecture and identify all required monitoring data sources
  • I understand how to design monitoring solutions based on business and security requirements
  • I can create Security Hub custom insights for automated audits
  • I know how to define appropriate metrics and thresholds for security alerts
  • I can design alerting workflows using CloudWatch, EventBridge, SNS, and Lambda

Troubleshooting Monitoring:

  • I can troubleshoot missing CloudWatch logs and identify permission issues
  • I understand how to diagnose EventBridge rules that aren't triggering
  • I can identify gaps in monitoring coverage and recommend solutions
  • I know how to troubleshoot custom application metrics not appearing in CloudWatch
  • I can evaluate monitoring alignment with security requirements

Logging Solutions:

  • I can configure CloudTrail, VPC Flow Logs, and CloudWatch Logs properly
  • I understand how to enable logging for all major AWS services (S3, ELB, WAF, Route 53)
  • I know how to implement centralized logging across multiple accounts
  • I can design log storage and lifecycle management strategies
  • I understand log encryption with KMS and access control with IAM

Troubleshooting Logging:

  • I can diagnose why CloudTrail events aren't being logged
  • I understand how to troubleshoot S3 bucket permission issues for log delivery
  • I can resolve KMS encryption issues preventing log delivery
  • I know how to identify and fix incomplete or missing logs
  • I can validate log integrity using CloudTrail log file validation

Log Analysis:

  • I can write Athena queries to analyze CloudTrail and VPC Flow Logs
  • I understand how to use CloudWatch Logs Insights for log analysis
  • I can create CloudWatch Logs filter patterns to extract specific events
  • I know how to use CloudTrail Insights to identify unusual API activity
  • I can correlate logs from multiple sources to investigate security events

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-25 (Monitoring and Logging Design)
  • Domain 2 Bundle 2: Questions 26-50 (Troubleshooting and Analysis)
  • Logging & Monitoring Services Bundle: Questions 1-50 (Service-specific scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review CloudTrail event structure and how to query with Athena
  • Practice writing CloudWatch metric filters and Logs Insights queries
  • Focus on understanding log delivery permissions and KMS encryption
  • Review centralized logging architectures for multi-account environments

Quick Reference Card

Key Services:

  • CloudTrail: API activity logging for all AWS services
  • VPC Flow Logs: Network traffic logging for VPCs, subnets, and ENIs
  • CloudWatch Logs: Centralized log aggregation and analysis
  • CloudWatch Metrics: Time-series metrics and alarms
  • Athena: SQL queries on logs stored in S3
  • CloudWatch Logs Insights: Interactive log analytics with query language

Key Concepts:

  • Organization Trail: Single CloudTrail trail that logs all accounts in AWS Organizations
  • Log File Validation: Cryptographic verification of CloudTrail log integrity
  • Metric Filter: Pattern matching on CloudWatch Logs to create metrics
  • Custom Insights: Security Hub queries to track specific security metrics
  • Log Lifecycle: Automated transition of logs through storage classes based on age

Decision Points:

  • Need API activity logs → CloudTrail (organization trail for multi-account)
  • Need network traffic logs → VPC Flow Logs (VPC level with custom format)
  • Need application logs → CloudWatch Logs (with appropriate retention)
  • Need to query logs → Athena (for S3) or CloudWatch Logs Insights (for CloudWatch Logs)
  • Need real-time alerting → CloudWatch metric filter + alarm + SNS
  • Need automated response → EventBridge rule + Lambda/Step Functions
  • Need log immutability → S3 Object Lock in compliance mode
  • Need centralized logging → Organization trail + S3 bucket with cross-account access

  • Real-time monitoring → CloudWatch Logs with metric filters and alarms
  • Historical analysis → Athena queries on S3-stored logs
  • Compliance logging → Organization Trail with log file validation
  • Application monitoring → CloudWatch Logs with custom metrics

Chapter Summary

What We Covered

This chapter covered Security Logging and Monitoring, the largest domain at 18% of the SCS-C02 exam. We explored five major task areas:

Task 2.1: Monitoring and Alerting Design

  • Analyzing architectures to identify monitoring requirements and data sources
  • Designing environment and workload monitoring based on business and security requirements
  • Setting up automated audits using Security Hub custom insights and scripts
  • Defining metrics and thresholds for CloudWatch alarms and anomaly detection

Task 2.2: Troubleshooting Monitoring and Alerting

  • Analyzing service configuration and permissions issues (Security Hub, GuardDuty, CloudWatch)
  • Troubleshooting custom application metrics and logging
  • Evaluating logging and monitoring solutions for alignment with security requirements

Task 2.3: Logging Solution Design and Implementation

  • Configuring logging for AWS services (CloudTrail, VPC Flow Logs, S3 access logs, ELB logs, WAF logs)
  • Identifying logging requirements and sources for comprehensive coverage
  • Implementing log storage and lifecycle management (S3, Glacier, retention policies)

Task 2.4: Troubleshooting Logging Solutions

  • Identifying misconfiguration and permission issues preventing log delivery
  • Determining the cause of missing logs and implementing remediation
  • Validating log integrity and investigating log delivery delays

Task 2.5: Log Analysis Solution Design

  • Using Athena and CloudWatch Logs filter for log analysis
  • Leveraging CloudWatch Logs Insights, CloudTrail Insights, and Security Hub insights
  • Identifying patterns in logs to detect anomalies and known threats
  • Normalizing, parsing, and correlating logs from multiple sources

Critical Takeaways

  1. CloudTrail is Mandatory: Every AWS account must have CloudTrail enabled with log file validation. Use Organization Trails for multi-account environments.

  2. Logging is Layered: Comprehensive security requires multiple log sources - CloudTrail (API calls), VPC Flow Logs (network traffic), CloudWatch Logs (application logs), and service-specific logs (S3, ELB, WAF).

  3. Centralize Everything: In multi-account environments, centralize logs to a dedicated logging account with restricted access and S3 Object Lock for immutability.

  4. Retention is Compliance: Different log types have different retention requirements. Use S3 Lifecycle policies to automatically transition logs through storage classes.

  5. Real-Time vs. Historical: CloudWatch is for real-time monitoring and alerting. Athena is for historical analysis and threat hunting on S3-stored logs.

  6. Metric Filters are Powerful: CloudWatch metric filters transform log data into metrics, enabling alarms and dashboards for security events.

  7. Athena Requires Partitioning: For efficient queries on large log datasets, partition by date and use columnar formats like Parquet.

  8. Log Integrity Matters: Enable CloudTrail log file validation to detect tampering. Use S3 Object Lock for immutable forensic evidence.

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Monitoring and Alerting:

  • Design a monitoring strategy for a multi-tier application on AWS
  • Identify which data sources are needed for specific security monitoring requirements
  • Create CloudWatch metric filters to detect security events (failed logins, unauthorized API calls)
  • Configure CloudWatch alarms with appropriate thresholds and SNS notifications
  • Set up Security Hub custom insights to track specific compliance metrics

Troubleshooting:

  • Diagnose why CloudTrail logs are not being delivered to S3
  • Troubleshoot missing VPC Flow Logs and identify permission issues
  • Investigate why a custom application is not sending metrics to CloudWatch
  • Resolve KMS encryption issues preventing log delivery

Logging Solutions:

  • Configure an Organization Trail for multi-account CloudTrail logging
  • Enable VPC Flow Logs for a VPC and send to CloudWatch Logs
  • Set up S3 access logging and configure lifecycle policies for log retention
  • Design a centralized logging architecture with log aggregation and immutability

Log Analysis:

  • Write Athena queries to search CloudTrail logs for specific API calls
  • Use CloudWatch Logs Insights to analyze application logs
  • Create partitioned tables in Athena for efficient log queries
  • Identify patterns in VPC Flow Logs indicating security threats

Decision-Making:

  • Choose between CloudWatch Logs and S3 for log storage based on requirements
  • Determine appropriate log retention periods for compliance
  • Select between CloudWatch Logs Insights and Athena for log analysis
  • Decide when to use CloudTrail Insights for anomaly detection

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-45 (focus on logging configuration and monitoring design)
  • Domain 2 Bundle 2: Questions 46-90 (focus on troubleshooting and log analysis)
  • Logging & Monitoring Services Bundle: Questions covering CloudTrail, CloudWatch, VPC Flow Logs, Config
  • Full Practice Test 1: Domain 2 questions (9 questions, 18% of exam)

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • CloudTrail Configuration (if you struggled with API logging questions)
    • VPC Flow Logs Analysis (if you struggled with network traffic questions)
    • CloudWatch Metric Filters (if you struggled with alerting questions)
    • Athena Query Optimization (if you struggled with log analysis questions)
  • Focus on:
    • Understanding the differences between CloudWatch Logs and S3 for log storage
    • Practicing Athena queries with partitioning for performance
    • Memorizing common CloudWatch metric filter patterns
    • Understanding log lifecycle management and retention policies

Quick Reference Card

Key Services:

  • CloudTrail: API activity logging for all AWS services (management events, data events, Insights events)
  • VPC Flow Logs: Network traffic logging for VPCs, subnets, and ENIs (accepted, rejected, all traffic)
  • CloudWatch Logs: Centralized log aggregation and analysis with retention policies
  • CloudWatch Metrics: Time-series metrics and alarms for monitoring and alerting
  • Athena: SQL queries on logs stored in S3 (serverless, pay-per-query)
  • CloudWatch Logs Insights: Interactive log analytics with query language (real-time)

Key Concepts:

  • Organization Trail: Single CloudTrail trail that logs all accounts in AWS Organizations
  • Log File Validation: Cryptographic verification of CloudTrail log integrity using digest files
  • Metric Filter: Pattern matching on CloudWatch Logs to create custom metrics
  • Custom Insights: Security Hub queries to track specific security metrics over time
  • Log Lifecycle: Automated transition of logs through storage classes (S3 → S3-IA → Glacier)
  • Partitioning: Organizing log data by date for efficient Athena queries

Decision Points:

  • Real-time monitoring → CloudWatch Logs with metric filters and alarms
  • Historical analysis → Athena queries on S3-stored logs
  • Compliance logging → Organization Trail with log file validation and S3 Object Lock
  • Application monitoring → CloudWatch Logs with custom metrics (embedded metrics format)
  • Cost optimization → S3 Lifecycle policies to transition old logs to Glacier
  • Multi-account logging → Centralized logging account with cross-account log delivery

Next Steps

Before moving to Domain 3:

  1. Review the Quick Reference Card and ensure you can recall all key services and logging sources
  2. Practice writing Athena queries on CloudTrail and VPC Flow Logs
  3. Experiment with CloudWatch Logs Insights queries
  4. Set up a personal Organization Trail if you have access to AWS Organizations

Moving Forward:

  • Domain 3 (Infrastructure Security) will cover the network and compute resources that generate the logs you learned about in this domain
  • Understanding VPC Flow Logs is essential for troubleshooting network security issues
  • CloudTrail logs will be critical for investigating IAM and access control issues in Domain 4

Chapter Summary

What We Covered

This chapter covered Domain 2: Security Logging and Monitoring (18% of the exam), focusing on five critical task areas:

Task 2.1: Design and implement monitoring and alerting

  • Analyzing architectures to identify monitoring requirements and data sources
  • Designing environment and workload monitoring based on business and security requirements
  • Setting up automated audits using Security Hub custom insights
  • Defining metrics and thresholds that generate alerts using CloudWatch and EventBridge

Task 2.2: Troubleshoot security monitoring and alerting

  • Analyzing service functionality, permissions, and configuration after events that didn't provide visibility
  • Analyzing and remediating custom application reporting issues
  • Evaluating logging and monitoring services for alignment with security requirements

Task 2.3: Design and implement a logging solution

  • Configuring logging for AWS services (CloudTrail, VPC Flow Logs, CloudWatch Logs, Route 53, S3, ELB, WAF)
  • Identifying logging requirements and sources for log ingestion
  • Implementing log storage and lifecycle management according to AWS best practices

Task 2.4: Troubleshoot logging solutions

  • Identifying misconfiguration and determining remediation steps for absent access permissions
  • Determining the cause of missing logs and performing remediation steps

Task 2.5: Design a log analysis solution

  • Using Athena and CloudWatch Logs filter for log analysis
  • Leveraging CloudWatch Logs Insights, CloudTrail Insights, and Security Hub insights
  • Identifying patterns in logs to indicate anomalies and known threats

Critical Takeaways

  1. CloudTrail is mandatory: Enable an Organization Trail to log all API calls across all accounts. Use log file validation and S3 Object Lock for compliance.

  2. VPC Flow Logs capture network traffic: Enable at VPC, subnet, or ENI level. Use for troubleshooting connectivity issues and detecting network-based attacks.

  3. CloudWatch Logs for application logs: Use the CloudWatch Logs agent or embedded metrics format to send application logs to CloudWatch.

  4. Athena for historical analysis: Query CloudTrail and VPC Flow Logs stored in S3 using Athena. Partition by date for performance.

  5. CloudWatch for real-time monitoring: Use metric filters to create custom metrics from logs, then create alarms to trigger notifications.

  6. Centralized logging architecture: Use a dedicated logging account with cross-account log delivery for security and compliance.

  7. Log lifecycle management: Use S3 Lifecycle policies to transition old logs to S3-IA and Glacier for cost optimization.

  8. Log immutability: Use S3 Object Lock (compliance mode) or Glacier Vault Lock to prevent log tampering for compliance.

  9. Security Hub custom insights: Create custom queries to track specific security metrics over time (e.g., failed login attempts, root account usage).

  10. CloudTrail Insights: Automatically detect unusual API activity (e.g., sudden spike in EC2 instance launches).

Self-Assessment Checklist

Test yourself before moving to Domain 3. You should be able to:

Monitoring and Alerting:

  • Design a monitoring strategy for a multi-tier web application
  • Identify appropriate data sources for security monitoring (CloudTrail, VPC Flow Logs, CloudWatch Logs)
  • Create CloudWatch metric filters to detect security events (e.g., root account usage, failed login attempts)
  • Design CloudWatch alarms with appropriate thresholds
  • Create Security Hub custom insights to track security metrics over time
  • Explain when to use CloudWatch vs. EventBridge for alerting

Troubleshooting Monitoring:

  • Troubleshoot missing CloudWatch Logs (check IAM permissions, log group configuration)
  • Troubleshoot EventBridge rules that aren't triggering (check event pattern, target configuration)
  • Troubleshoot custom application metrics not appearing in CloudWatch (check IAM permissions, SDK configuration)
  • Identify gaps in security monitoring coverage

Logging Solutions:

  • Enable CloudTrail with log file validation and S3 Object Lock
  • Enable VPC Flow Logs at VPC, subnet, and ENI levels
  • Configure CloudWatch Logs retention policies
  • Design a centralized logging architecture for multi-account environments
  • Implement S3 Lifecycle policies for log archival
  • Explain the difference between CloudTrail data events and management events

Troubleshooting Logging:

  • Troubleshoot missing CloudTrail logs (check S3 bucket permissions, KMS key policy, trail configuration)
  • Troubleshoot missing VPC Flow Logs (check IAM role, log destination permissions)
  • Troubleshoot log delivery delays
  • Validate CloudTrail log file integrity using digest files

Log Analysis:

  • Write Athena queries to search CloudTrail logs for specific API calls
  • Write Athena queries to analyze VPC Flow Logs for network traffic patterns
  • Use CloudWatch Logs Insights to query application logs
  • Interpret CloudTrail Insights findings
  • Create Security Hub custom insights for compliance tracking
  • Explain how to partition logs in S3 for efficient Athena queries

Practice Questions

Recommended Practice Test Bundles:

  • Domain 2 Bundle 1: Questions 71-120 (covers all Task 2.1, 2.2, 2.3, 2.4, 2.5 topics)
  • Domain 2 Bundle 2: Questions 121-160 (additional practice on weak areas)
  • Logging & Monitoring Services Bundle: Questions covering CloudTrail, CloudWatch, VPC Flow Logs, Config

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • CloudTrail Architecture (if you struggled with trail configuration questions)
    • VPC Flow Logs Analysis (if you struggled with network troubleshooting questions)
    • Athena Query Optimization (if you struggled with log analysis questions)
    • CloudWatch Metric Filters (if you struggled with real-time monitoring questions)
  • Focus on:
    • Understanding the difference between CloudTrail management events and data events
    • Practicing Athena queries on CloudTrail and VPC Flow Logs
    • Memorizing CloudWatch Logs Insights query syntax
    • Understanding S3 Lifecycle policies for log archival

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • CloudTrail: API call logging (management events and data events)
  • VPC Flow Logs: Network traffic logging (accepted, rejected, or all traffic)
  • CloudWatch Logs: Application and system logs
  • CloudWatch Metrics: Time-series data for monitoring
  • CloudWatch Alarms: Notifications based on metric thresholds
  • Athena: SQL queries on S3-stored logs
  • CloudWatch Logs Insights: Query language for CloudWatch Logs

Key Concepts:

  • Organization Trail: Single CloudTrail trail that logs all accounts in AWS Organizations
  • Log File Validation: Cryptographic verification of CloudTrail log integrity using digest files
  • Metric Filter: Pattern matching on CloudWatch Logs to create custom metrics
  • Custom Insights: Security Hub queries to track specific security metrics over time
  • Log Lifecycle: Automated transition of logs through storage classes (S3 → S3-IA → Glacier)
  • Partitioning: Organizing log data by date for efficient Athena queries

Decision Points:

  • Real-time monitoring → CloudWatch Logs with metric filters and alarms
  • Historical analysis → Athena queries on S3-stored logs
  • Compliance logging → Organization Trail with log file validation and S3 Object Lock
  • Application monitoring → CloudWatch Logs with custom metrics (embedded metrics format)
  • Cost optimization → S3 Lifecycle policies to transition old logs to Glacier
  • Multi-account logging → Centralized logging account with cross-account log delivery

Common Patterns:

  • CloudTrail → S3 → Athena (historical analysis)
  • CloudWatch Logs → Metric Filter → Alarm → SNS (real-time alerting)
  • VPC Flow Logs → S3 → Athena (network analysis)
  • CloudTrail Insights → EventBridge → Lambda (unusual activity response)
  • Security Hub → Custom Insights → Dashboard (compliance tracking)

Chapter Summary

What We Covered

This chapter covered Domain 2: Security Logging and Monitoring (18% of the exam), focusing on five critical task areas:

Task 2.1: Design and implement monitoring and alerting

  • Analyzing architectures to identify monitoring requirements and data sources
  • Designing environment and workload monitoring based on business and security requirements
  • Setting up automated audits using Security Hub custom insights and Config rules
  • Defining metrics and thresholds for CloudWatch alarms and anomaly detection

Task 2.2: Troubleshoot security monitoring and alerting

  • Analyzing service configuration and permissions when monitoring fails
  • Troubleshooting custom application metrics and logging
  • Evaluating logging and monitoring services for alignment with security requirements

Task 2.3: Design and implement a logging solution

  • Configuring logging for AWS services (CloudTrail, VPC Flow Logs, S3 access logs, ELB logs, WAF logs)
  • Identifying logging requirements and sources for log ingestion
  • Implementing log storage and lifecycle management with S3 and CloudWatch Logs

Task 2.4: Troubleshoot logging solutions

  • Identifying misconfiguration and missing permissions for logging
  • Determining the cause of missing logs and performing remediation
  • Validating log integrity and delivery

Task 2.5: Design a log analysis solution

  • Using Athena and CloudWatch Logs filter for log analysis
  • Leveraging CloudWatch Logs Insights, CloudTrail Insights, and Security Hub insights
  • Identifying patterns in logs to detect anomalies and known threats
  • Normalizing, parsing, and correlating logs from multiple sources

Critical Takeaways

  1. CloudTrail is mandatory: Enable organization trail for all accounts and regions. It's the audit log for all API calls and is required for compliance.

  2. VPC Flow Logs capture network traffic: Enable at VPC, subnet, or ENI level. Essential for investigating network-based attacks and unauthorized access.

  3. CloudWatch is the central monitoring hub: Metrics, logs, alarms, dashboards, and anomaly detection all live in CloudWatch.

  4. Log retention varies by service: CloudTrail logs in S3 (indefinite), CloudWatch Logs (configurable 1 day to 10 years), VPC Flow Logs (CloudWatch or S3).

  5. Athena enables SQL queries on logs: Query CloudTrail, VPC Flow Logs, and other logs stored in S3 using standard SQL. Partition by date for performance.

  6. Metric filters extract metrics from logs: Create CloudWatch metric filters to count specific log patterns (failed logins, API errors, security events).

  7. Composite alarms reduce noise: Combine multiple alarms with AND/OR logic to trigger only when multiple conditions are met.

  8. CloudTrail Insights detects unusual API activity: Automatically identifies anomalous API call patterns using machine learning.

  9. Log immutability prevents tampering: Use S3 Object Lock or CloudWatch Logs encryption to ensure logs cannot be modified or deleted.

  10. Centralized logging is essential: Aggregate logs from all accounts into a central security account for analysis and long-term retention.

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Monitoring and Alerting:

  • Design a monitoring strategy for a multi-tier web application
  • Create a CloudWatch alarm that triggers when failed login attempts exceed a threshold
  • Configure a Security Hub custom insight to track unencrypted S3 buckets
  • Set up CloudWatch anomaly detection for baseline deviation alerts
  • Design a composite alarm that triggers only when multiple security conditions are met

Troubleshooting Monitoring:

  • Diagnose why GuardDuty is not detecting threats in a specific account
  • Fix missing CloudWatch Logs due to IAM permission issues
  • Troubleshoot an EventBridge rule that's not triggering Lambda functions
  • Identify why custom application metrics are not appearing in CloudWatch
  • Resolve Config recorder issues preventing compliance tracking

Logging Solutions:

  • Enable an organization trail that logs all accounts and regions
  • Configure VPC Flow Logs to capture accepted, rejected, and all traffic
  • Set up S3 access logging with proper bucket permissions
  • Enable WAF logging to Kinesis Data Firehose for real-time analysis
  • Design a log lifecycle policy that archives logs to Glacier after 90 days

Troubleshooting Logging:

  • Diagnose why CloudTrail is not logging events to S3
  • Fix VPC Flow Logs that are missing due to IAM role issues
  • Resolve KMS encryption errors preventing log delivery
  • Troubleshoot cross-account logging failures
  • Validate CloudTrail log file integrity using digest files

Log Analysis:

  • Write an Athena query to find all S3 bucket deletions in the last 30 days
  • Create a CloudWatch Logs Insights query to find failed API calls
  • Use CloudTrail Insights to identify unusual API activity
  • Design a log correlation strategy to link events across multiple services
  • Normalize and parse logs from different sources for unified analysis

Practice Questions

Try these from your practice test bundles:

  • Domain 2 Bundle 1: Questions 1-25 (focus on monitoring and logging design)
  • Domain 2 Bundle 2: Questions 26-50 (focus on troubleshooting and analysis)
  • Logging Monitoring Services Bundle: Questions covering CloudTrail, CloudWatch, VPC Flow Logs, Config
  • Full Practice Test 1: Domain 2 questions (9 questions, 18% of exam)

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review the differences between CloudTrail, VPC Flow Logs, and CloudWatch Logs
  • Practice writing Athena queries on sample CloudTrail logs
  • Focus on understanding IAM permissions required for logging
  • Revisit the log aggregation and centralization architectures

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • CloudTrail: API call audit logs (who did what, when, where)
  • VPC Flow Logs: Network traffic logs (source, destination, ports, protocols)
  • CloudWatch Logs: Application and system logs with retention policies
  • CloudWatch Metrics: Time-series data for monitoring and alarms
  • CloudWatch Alarms: Notifications when metrics exceed thresholds
  • Athena: SQL queries on logs stored in S3
  • CloudWatch Logs Insights: Query language for CloudWatch Logs

Key Concepts:

  • Organization Trail: CloudTrail trail that logs all accounts in an organization
  • Metric Filter: Extracts metrics from CloudWatch Logs based on patterns
  • Composite Alarm: Combines multiple alarms with AND/OR logic
  • CloudTrail Insights: ML-based detection of unusual API activity
  • Log Immutability: S3 Object Lock or encryption to prevent log tampering
  • Centralized Logging: Aggregating logs from all accounts into a security account

Decision Points:

  • Need API audit logs → CloudTrail (organization trail for all accounts)
  • Need network traffic logs → VPC Flow Logs (enable at VPC or subnet level)
  • Need application logs → CloudWatch Logs (configure log groups and retention)
  • Need to query logs → Athena (for S3) or CloudWatch Logs Insights (for CloudWatch)
  • Need to detect anomalies → CloudWatch anomaly detection or CloudTrail Insights
  • Need to alert on events → CloudWatch alarms with SNS notifications

Common Troubleshooting:

  • CloudTrail not logging → Check S3 bucket policy, KMS key policy, IAM permissions
  • VPC Flow Logs missing → Check IAM role, CloudWatch Logs permissions, flow log configuration
  • Alarms not triggering → Check metric filter pattern, alarm threshold, SNS topic permissions
  • Logs not appearing → Check service configuration, IAM permissions, log delivery delay

You're now ready for Chapter 3: Infrastructure Security!

The next chapter will teach you how to secure the network and compute resources that generate the logs you just learned about.


Chapter 3: Infrastructure Security (20% of exam)

Chapter Overview

What you'll learn:

  • How to design and implement security controls for edge services (WAF, Shield, CloudFront)
  • Network security controls including VPC, security groups, NACLs, and Network Firewall
  • Compute workload security for EC2, containers, and serverless
  • Network troubleshooting techniques and tools

Time to complete: 12-15 hours
Prerequisites: Chapter 0 (Fundamentals), Chapter 2 (Logging basics)

Why this domain matters: Infrastructure security is the foundation of AWS security. This domain represents 20% of the exam (the largest single domain) and tests your ability to design secure network architectures, protect against common attacks, secure compute workloads, and troubleshoot network security issues. Mastering this domain is critical for exam success.


Section 1: Edge Security - AWS WAF and Shield

Introduction

The problem: Web applications face constant attacks from the internet: SQL injection, cross-site scripting (XSS), DDoS attacks, and bot traffic. Without protection at the edge, these attacks reach your application servers, consuming resources and potentially compromising security.

The solution: AWS provides edge security services that filter malicious traffic before it reaches your infrastructure. AWS WAF (Web Application Firewall) protects against application-layer attacks, while AWS Shield protects against DDoS attacks. Together, they form a defense-in-depth strategy at the edge.

Why it's tested: Edge security is the first line of defense for internet-facing applications. The exam tests your understanding of how to configure WAF rules, protect against OWASP Top 10 vulnerabilities, mitigate DDoS attacks, and design layered edge security architectures.

Core Concepts

AWS WAF - Web Application Firewall

What it is: AWS WAF is a web application firewall that protects your web applications from common web exploits by filtering HTTP/HTTPS requests based on rules you define. It integrates with CloudFront, Application Load Balancer, API Gateway, and AppSync.

Why it exists: Traditional network firewalls operate at layers 3-4 (IP and transport), but web attacks occur at layer 7 (application). WAF inspects HTTP requests and blocks malicious patterns like SQL injection attempts, XSS payloads, and bot traffic before they reach your application.

Real-world analogy: AWS WAF is like a security guard at a building entrance who checks IDs and bags. Just as the guard stops suspicious individuals before they enter, WAF stops malicious requests before they reach your application servers.

How it works (Detailed step-by-step):

  1. Request Arrival: A client sends an HTTP/HTTPS request to your application through CloudFront or ALB.
  2. WAF Evaluation: Before forwarding the request, WAF evaluates it against Web ACLs (Access Control Lists) containing rules.
  3. Rule Matching: WAF checks the request against each rule in priority order. Rules can inspect request components: URI, query strings, headers, body, cookies, and HTTP method.
  4. Action Determination: When a rule matches, WAF takes the specified action: ALLOW (forward request), BLOCK (return 403 Forbidden), COUNT (count but allow), or CAPTCHA (challenge with CAPTCHA).
  5. Request Forwarding or Blocking: If allowed, the request proceeds to your application. If blocked, WAF returns an error response immediately.
  6. Logging: WAF logs all requests (allowed and blocked) to CloudWatch Logs or S3 for analysis.
  7. Metrics: WAF publishes metrics to CloudWatch showing request counts, blocked requests, and rule matches.

📊 AWS WAF Architecture Diagram:

graph TB
    Internet[Internet Users]
    
    subgraph "Edge Layer"
        CF[CloudFront Distribution]
        WAF[AWS WAF<br/>Web ACL]
    end
    
    subgraph "Application Layer"
        ALB[Application Load Balancer]
        EC2_1[EC2 Instance 1]
        EC2_2[EC2 Instance 2]
    end
    
    subgraph "WAF Rules"
        ManagedRules[AWS Managed Rules]
        CustomRules[Custom Rules]
        RateLimit[Rate Limiting]
        GeoBlock[Geo Blocking]
    end
    
    Logs[CloudWatch Logs<br/>WAF Logs]
    
    Internet --> CF
    CF --> WAF
    WAF --> ALB
    ALB --> EC2_1
    ALB --> EC2_2
    
    ManagedRules -.-> WAF
    CustomRules -.-> WAF
    RateLimit -.-> WAF
    GeoBlock -.-> WAF
    
    WAF -->|Logs| Logs
    
    style WAF fill:#c8e6c9
    style CF fill:#e1f5fe
    style ALB fill:#fff3e0
    style Logs fill:#f3e5f5

See: diagrams/04_domain3_waf_architecture.mmd

Diagram Explanation (Detailed):

The diagram shows a complete edge security architecture using AWS WAF. Internet users send requests to a CloudFront distribution, which acts as the entry point. Before CloudFront forwards requests to the origin (Application Load Balancer), AWS WAF evaluates each request against a Web ACL containing multiple rule types. AWS Managed Rules provide pre-configured protection against OWASP Top 10 vulnerabilities. Custom Rules implement application-specific security logic. Rate Limiting rules prevent abuse by limiting requests per IP address. Geo Blocking rules restrict access based on geographic location. When WAF blocks a request, it returns a 403 error immediately without reaching the ALB or EC2 instances. All requests (allowed and blocked) are logged to CloudWatch Logs for security analysis. This layered architecture protects applications from web attacks at the edge, reducing load on backend servers and preventing exploitation.

Detailed Example 1: Protecting Against SQL Injection

An e-commerce company wants to protect their web application from SQL injection attacks. Here's how they use AWS WAF: (1) They create a Web ACL and attach it to their Application Load Balancer. (2) They add the AWS Managed Rule Group "AWSManagedRulesSQLiRuleSet" which contains rules to detect SQL injection patterns. (3) They configure the rule group action to BLOCK. (4) An attacker attempts to exploit a search feature by submitting: search.php?query=' OR '1'='1. (5) WAF inspects the query string and detects the SQL injection pattern ' OR '1'='1. (6) WAF blocks the request and returns a 403 Forbidden response. (7) The attack never reaches the application servers. (8) WAF logs the blocked request to CloudWatch Logs, including the attacker's IP address and the malicious payload. (9) The security team reviews WAF logs and adds the attacker's IP to a custom IP set for permanent blocking. AWS WAF prevented the SQL injection attack at the edge, protecting the database from unauthorized access.

Detailed Example 2: Mitigating Bot Traffic

A media company's website is experiencing high traffic from bots scraping content. Here's how they use AWS WAF: (1) They create a Web ACL with the AWS Managed Rule Group "AWSManagedRulesBotControlRuleSet". (2) This rule group uses machine learning to identify bot traffic patterns. (3) They configure a rate-based rule that blocks IPs making more than 2,000 requests in 5 minutes. (4) They add a CAPTCHA challenge for suspicious requests instead of outright blocking. (5) Legitimate users occasionally trigger the CAPTCHA but can proceed after solving it. (6) Bots cannot solve CAPTCHAs and are effectively blocked. (7) WAF metrics show a 70% reduction in bot traffic. (8) The company's infrastructure costs decrease as fewer requests reach their servers. (9) Legitimate user experience improves due to reduced server load. AWS WAF's bot control and rate limiting protected the site from bot abuse while maintaining access for legitimate users.

Detailed Example 3: Geo-Blocking for Compliance

A financial services company must restrict access to their application to users in the United States only (compliance requirement). Here's how they use AWS WAF: (1) They create a Web ACL with a geo-match rule that blocks requests from countries other than the US. (2) They configure the rule to inspect the CloudFront-Viewer-Country header (automatically added by CloudFront). (3) The rule action is set to BLOCK for all countries except US. (4) A user in Russia attempts to access the application. (5) CloudFront adds the header CloudFront-Viewer-Country: RU to the request. (6) WAF evaluates the geo-match rule, sees the country is Russia (not US), and blocks the request. (7) The user receives a 403 Forbidden response with a custom error page explaining access is restricted. (8) WAF logs show blocked requests from 50+ countries. (9) The company demonstrates compliance by showing WAF logs to auditors. AWS WAF's geo-blocking capability enabled the company to meet regulatory requirements by restricting access based on geographic location.

Must Know (Critical Facts):

  • WAF operates at Layer 7 (application layer), inspecting HTTP/HTTPS requests, not network traffic
  • Web ACLs contain rules evaluated in priority order - first matching rule determines the action
  • AWS Managed Rule Groups provide pre-configured protection against OWASP Top 10 and common threats
  • Rate-based rules limit requests per IP address per 5-minute period - essential for DDoS mitigation
  • CAPTCHA challenges allow legitimate users to proceed while blocking bots
  • WAF can inspect request components: URI, query string, headers, body (first 8 KB), cookies, HTTP method
  • WAF pricing is based on Web ACLs, rules, and requests processed - can be expensive at high scale

When to use (Comprehensive):

  • ✅ Use AWS WAF when: You have internet-facing web applications that need protection from OWASP Top 10 vulnerabilities
  • ✅ Use AWS WAF when: You want to block bot traffic, scrapers, or abusive users
  • ✅ Use AWS WAF when: You need to implement rate limiting to prevent abuse or DDoS attacks
  • ✅ Use AWS WAF when: You must restrict access based on geographic location for compliance
  • ✅ Use AWS WAF when: You want to create custom security rules based on your application's specific needs
  • ❌ Don't use AWS WAF when: You only need network-level filtering (use security groups and NACLs instead)
  • ❌ Don't use AWS WAF when: Your application is not internet-facing (internal applications don't need edge protection)
  • ❌ Don't use AWS WAF when: Cost is a major concern and traffic volume is extremely high (consider alternative solutions)

AWS Shield - DDoS Protection

What it is: AWS Shield is a managed DDoS (Distributed Denial of Service) protection service that safeguards applications running on AWS. Shield Standard provides automatic protection against common network and transport layer attacks. Shield Advanced provides enhanced protection and 24/7 access to the AWS DDoS Response Team (DRT).

Why it exists: DDoS attacks overwhelm applications with massive traffic volumes, making them unavailable to legitimate users. Shield protects against these attacks by detecting and mitigating malicious traffic automatically.

Real-world analogy: Shield is like a flood control system for your application. Just as flood barriers protect buildings from water surges, Shield protects your application from traffic surges caused by DDoS attacks.

How it works (Detailed step-by-step):

  1. Traffic Monitoring: Shield continuously monitors traffic patterns to your AWS resources (CloudFront, Route 53, ALB, ELB, Elastic IP).
  2. Baseline Learning: Shield learns normal traffic patterns for your application over time.
  3. Anomaly Detection: When traffic volume or patterns deviate significantly from the baseline, Shield detects a potential DDoS attack.
  4. Automatic Mitigation: Shield Standard automatically mitigates common layer 3/4 attacks (SYN floods, UDP reflection attacks) without any configuration.
  5. Advanced Mitigation (Shield Advanced only): For sophisticated attacks, Shield Advanced applies custom mitigation rules and engages the DDoS Response Team.
  6. Traffic Scrubbing: Malicious traffic is filtered out while legitimate traffic continues to flow to your application.
  7. Real-time Metrics: Shield publishes metrics to CloudWatch showing attack volume, mitigation status, and traffic patterns.

Detailed Example 1: Mitigating a SYN Flood Attack

An online gaming company experiences a SYN flood attack targeting their game servers. Here's how Shield protects them: (1) Attackers send millions of SYN packets to the company's Elastic IP addresses, attempting to exhaust server resources. (2) Shield Standard (enabled by default) detects the abnormal SYN packet volume. (3) Shield automatically activates mitigation, filtering out malicious SYN packets at the AWS edge. (4) Legitimate player traffic continues to reach the game servers without interruption. (5) The attack lasts 2 hours, but players experience no downtime. (6) Shield metrics show 50 million malicious packets were blocked. (7) The company didn't need to take any action - Shield protected them automatically. AWS Shield Standard provided automatic protection against the layer 4 DDoS attack at no additional cost.

Detailed Example 2: Advanced Protection with Shield Advanced

An e-commerce company upgrades to Shield Advanced for enhanced protection during Black Friday sales. Here's how it helps: (1) They enable Shield Advanced on their CloudFront distribution and Application Load Balancers. (2) During Black Friday, attackers launch a sophisticated layer 7 DDoS attack, sending millions of HTTP requests that mimic legitimate traffic. (3) Shield Advanced detects the attack using advanced heuristics and machine learning. (4) The AWS DDoS Response Team (DRT) is automatically notified and begins monitoring the attack. (5) DRT creates custom WAF rules to filter the attack traffic while allowing legitimate shoppers. (6) The attack is mitigated within 15 minutes. (7) Shield Advanced provides cost protection - the company doesn't pay for the attack traffic that scaled their infrastructure. (8) Post-attack, DRT provides a detailed report and recommendations. Shield Advanced's enhanced protection and expert support ensured the company's Black Friday sales were not disrupted.

Detailed Example 3: DNS DDoS Protection

A SaaS company's website becomes unreachable due to a DNS amplification attack. Here's how Shield protects them: (1) Attackers exploit misconfigured DNS servers to send massive DNS responses to the company's Route 53 hosted zone. (2) Shield detects the abnormal DNS query volume and response sizes. (3) Shield automatically filters malicious DNS traffic at AWS edge locations. (4) Legitimate DNS queries continue to be resolved normally. (5) The company's website remains accessible throughout the attack. (6) Shield metrics show 100 GB of malicious DNS traffic was blocked. (7) The company's DNS infrastructure was never overwhelmed. AWS Shield's automatic DNS protection prevented the amplification attack from affecting availability.

Must Know (Critical Facts):

  • Shield Standard is automatically enabled for all AWS customers at no additional cost
  • Shield Standard protects against common layer 3/4 DDoS attacks (SYN floods, UDP reflection, etc.)
  • Shield Advanced costs $3,000/month but provides enhanced protection, DDoS cost protection, and 24/7 DRT access
  • Shield Advanced integrates with WAF to provide layer 7 DDoS protection
  • Shield Advanced provides DDoS cost protection - you don't pay for scaling costs during attacks
  • Shield Advanced includes health-based detection that monitors application health metrics to detect attacks
  • Shield works best when combined with WAF, CloudFront, and Route 53 for defense-in-depth

Section 2: VPC Security - Network Segmentation

Introduction

The problem: Without proper network segmentation, a compromised resource can access all other resources in your network. Attackers can move laterally, escalating their access and compromising additional systems.

The solution: Amazon VPC (Virtual Private Cloud) provides network isolation and segmentation capabilities. Security groups and Network ACLs (NACLs) control traffic flow between resources, implementing the principle of least privilege at the network level.

Why it's tested: VPC security is fundamental to AWS infrastructure security. The exam tests your ability to design secure network architectures, configure security groups and NACLs correctly, and troubleshoot network connectivity issues.

Core Concepts

Security Groups - Stateful Firewalls

What it is: Security groups are stateful firewalls that control inbound and outbound traffic at the instance level (network interface). They act as virtual firewalls for EC2 instances, RDS databases, and other resources.

Why it exists: Every resource needs network-level access control to prevent unauthorized connections. Security groups provide this control with a simple, stateful model that automatically allows return traffic.

Real-world analogy: Security groups are like bouncers at a club entrance. They check IDs (source IPs) and decide who can enter (inbound rules) and who can leave (outbound rules). Once someone is inside, they can leave freely (stateful - return traffic is automatically allowed).

How it works (Detailed step-by-step):

  1. Rule Definition: You define inbound and outbound rules specifying allowed traffic by protocol, port, and source/destination.
  2. Traffic Arrival: When traffic arrives at a network interface, the security group evaluates inbound rules.
  3. Rule Evaluation: Security groups evaluate all rules (no priority order) and allow traffic if ANY rule matches.
  4. Connection Tracking: When inbound traffic is allowed, the security group automatically allows return traffic (stateful behavior).
  5. Outbound Evaluation: For outbound traffic, security groups evaluate outbound rules and automatically allow return traffic.
  6. Default Deny: If no rule matches, traffic is implicitly denied (default deny).
  7. Logging: Security groups don't log traffic directly - use VPC Flow Logs to see allowed/rejected traffic.

📊 VPC Security Architecture Diagram:

graph TB
    subgraph "VPC: 10.0.0.0/16"
        subgraph "Public Subnet: 10.0.1.0/24"
            IGW[Internet Gateway]
            ALB[Application Load Balancer]
            SG_ALB[Security Group: ALB<br/>Allow 80/443 from 0.0.0.0/0]
        end
        
        subgraph "Private Subnet: 10.0.2.0/24"
            EC2_1[EC2 Web Server 1]
            EC2_2[EC2 Web Server 2]
            SG_Web[Security Group: Web<br/>Allow 80 from SG_ALB]
        end
        
        subgraph "Database Subnet: 10.0.3.0/24"
            RDS[RDS Database]
            SG_DB[Security Group: DB<br/>Allow 3306 from SG_Web]
        end
        
        NACL_Public[NACL: Public<br/>Allow 80/443 inbound<br/>Allow ephemeral outbound]
        NACL_Private[NACL: Private<br/>Allow from VPC only]
    end
    
    Internet[Internet]
    
    Internet --> IGW
    IGW --> ALB
    ALB --> EC2_1
    ALB --> EC2_2
    EC2_1 --> RDS
    EC2_2 --> RDS
    
    SG_ALB -.-> ALB
    SG_Web -.-> EC2_1
    SG_Web -.-> EC2_2
    SG_DB -.-> RDS
    
    NACL_Public -.-> ALB
    NACL_Private -.-> EC2_1
    NACL_Private -.-> EC2_2
    NACL_Private -.-> RDS
    
    style SG_ALB fill:#c8e6c9
    style SG_Web fill:#e1f5fe
    style SG_DB fill:#fff3e0
    style NACL_Public fill:#f3e5f5
    style NACL_Private fill:#ffebee

See: diagrams/04_domain3_vpc_security.mmd

Diagram Explanation (Detailed):

The diagram illustrates a secure three-tier VPC architecture with defense-in-depth using security groups and NACLs. The VPC (10.0.0.0/16) is divided into three subnets: public (10.0.1.0/24) for the ALB, private (10.0.2.0/24) for web servers, and database (10.0.3.0/24) for RDS. Internet traffic enters through the Internet Gateway and reaches the ALB in the public subnet. The ALB's security group (SG_ALB) allows inbound traffic on ports 80/443 from anywhere (0.0.0.0/0). The ALB forwards requests to EC2 web servers in the private subnet. The web servers' security group (SG_Web) only allows traffic on port 80 from SG_ALB (not from the internet directly), implementing the principle of least privilege. Web servers connect to the RDS database in the database subnet. The database security group (SG_DB) only allows traffic on port 3306 from SG_Web, ensuring only web servers can access the database. NACLs provide an additional layer of defense: the public subnet NACL allows HTTP/HTTPS inbound and ephemeral ports outbound, while the private subnet NACL only allows traffic from within the VPC. This layered architecture prevents direct internet access to web servers and databases, limits lateral movement, and implements defense-in-depth.

Detailed Example 1: Implementing Least Privilege with Security Groups

A company wants to ensure their web servers can only be accessed through the load balancer. Here's how they use security groups: (1) They create three security groups: SG-ALB for the load balancer, SG-Web for web servers, and SG-DB for the database. (2) SG-ALB allows inbound traffic on ports 80 and 443 from 0.0.0.0/0 (internet). (3) SG-Web allows inbound traffic on port 80 ONLY from SG-ALB (not from the internet). (4) SG-DB allows inbound traffic on port 3306 ONLY from SG-Web. (5) An attacker discovers a web server's private IP address and attempts to connect directly. (6) The connection is blocked because SG-Web only allows traffic from SG-ALB, not from arbitrary IPs. (7) The attacker cannot bypass the load balancer to reach web servers directly. (8) Similarly, even if a web server is compromised, the attacker cannot access the database from other sources because SG-DB only allows traffic from SG-Web. Security groups implemented defense-in-depth by restricting traffic flow to only necessary paths.

Detailed Example 2: Troubleshooting Security Group Issues

A developer cannot connect to an EC2 instance via SSH. Here's how they troubleshoot using security groups: (1) They check the instance's security group and see it allows SSH (port 22) from 0.0.0.0/0. (2) They verify their source IP is 203.0.113.45 and should be allowed. (3) They check VPC Flow Logs and see REJECT for their SSH attempts. (4) They realize the security group allows SSH, but a Network ACL might be blocking it. (5) They check the subnet's NACL and discover it only allows ports 80 and 443, not port 22. (6) They update the NACL to allow port 22 inbound and ephemeral ports (1024-65535) outbound for return traffic. (7) They try SSH again and successfully connect. (8) VPC Flow Logs now show ACCEPT for SSH traffic. The issue was the NACL blocking SSH, not the security group. This demonstrates the importance of checking both security groups and NACLs when troubleshooting connectivity.

Detailed Example 3: Preventing Data Exfiltration with Outbound Rules

A security team wants to prevent compromised instances from exfiltrating data to external servers. Here's how they use security group outbound rules: (1) By default, security groups allow all outbound traffic. (2) They create a restrictive security group that only allows outbound traffic to specific destinations: the company's S3 bucket (via VPC endpoint), internal RDS databases, and approved external APIs. (3) They remove the default "allow all outbound" rule. (4) An attacker compromises an EC2 instance and attempts to send stolen data to an external server at 198.51.100.50. (5) The security group blocks the outbound connection because 198.51.100.50 is not in the allowed destinations. (6) The attacker cannot exfiltrate data. (7) VPC Flow Logs show REJECT for the outbound connection attempt, alerting the security team. (8) The team investigates and discovers the compromised instance. Restrictive outbound security group rules prevented data exfiltration even after the instance was compromised.

Must Know (Critical Facts):

  • Security groups are stateful - return traffic is automatically allowed regardless of outbound rules
  • Security groups use implicit deny - if no rule allows traffic, it's blocked
  • Security groups evaluate ALL rules (no priority) - if ANY rule matches, traffic is allowed
  • You can reference other security groups in rules (e.g., "allow traffic from SG-Web") for dynamic, scalable security
  • Security groups can only ALLOW traffic, never explicitly DENY - use NACLs for explicit deny rules
  • Changes to security groups take effect immediately
  • Security groups are associated with network interfaces, not instances - an instance can have multiple security groups

Network ACLs - Stateless Firewalls

What it is: Network ACLs (NACLs) are stateless firewalls that control traffic at the subnet level. They provide an additional layer of defense beyond security groups.

Why it exists: Security groups protect individual instances, but NACLs protect entire subnets. They provide defense-in-depth and enable explicit deny rules that security groups cannot provide.

Real-world analogy: If security groups are bouncers at individual club entrances, NACLs are security checkpoints at the neighborhood entrance. Everyone entering the neighborhood must pass the checkpoint before reaching individual clubs.

How it works (Detailed step-by-step):

  1. Rule Definition: You define numbered rules (1-32766) with allow or deny actions for inbound and outbound traffic.
  2. Rule Evaluation: NACLs evaluate rules in numerical order (lowest to highest) and stop at the first matching rule.
  3. Stateless Behavior: Unlike security groups, NACLs are stateless - you must explicitly allow return traffic with separate rules.
  4. Subnet Association: Each subnet must be associated with exactly one NACL (default NACL if not specified).
  5. Traffic Filtering: NACLs filter traffic entering and leaving the subnet, providing subnet-level protection.
  6. Default Deny: If no rule matches, traffic is denied (rule * with deny action).

Detailed Example 1: Blocking Malicious IPs with NACLs

A company detects attacks from specific IP addresses. Here's how they use NACLs: (1) They identify attacker IPs from VPC Flow Logs: 203.0.113.45 and 203.0.113.46. (2) They cannot use security groups to block these IPs because security groups only allow, never deny. (3) They update the subnet's NACL to add explicit deny rules: Rule 10: DENY TCP from 203.0.113.45 on all ports, Rule 20: DENY TCP from 203.0.113.46 on all ports. (4) They place these rules before the allow rules (which start at rule 100). (5) The attackers attempt to connect but are blocked at the subnet level. (6) VPC Flow Logs show REJECT for traffic from these IPs. (7) Legitimate traffic continues to flow normally. NACLs provided the explicit deny capability needed to block specific malicious IPs.

Detailed Example 2: Understanding Stateless Behavior

A developer configures a NACL but forgets about stateless behavior. Here's what happens: (1) They create a NACL rule allowing inbound HTTP (port 80) from 0.0.0.0/0. (2) They test the web application and it doesn't work. (3) They check security groups - all correct. (4) They realize NACLs are stateless and need explicit outbound rules for return traffic. (5) HTTP responses use ephemeral ports (1024-65535), not port 80. (6) They add an outbound rule allowing TCP ports 1024-65535 to 0.0.0.0/0. (7) The application now works. (8) They learn that NACLs require both inbound and outbound rules for bidirectional communication. This example demonstrates the critical difference between stateful security groups and stateless NACLs.

Must Know (Critical Facts):

  • NACLs are stateless - you must explicitly allow return traffic with separate rules
  • NACLs evaluate rules in numerical order and stop at the first match - rule order matters
  • NACLs can explicitly DENY traffic - use this to block specific IPs or ports
  • Each subnet has exactly one NACL - default NACL allows all traffic
  • NACL rules are evaluated before security group rules - NACLs provide subnet-level protection
  • Ephemeral ports (1024-65535) must be allowed outbound for return traffic
  • NACLs are best for subnet-level protection and explicit denies, not fine-grained instance-level control

Section 3: Compute Security

EC2 Security Best Practices

Patching and Vulnerability Management:

What it is: Keeping EC2 instances updated with the latest security patches to protect against known vulnerabilities.

Why it matters: Unpatched systems are the #1 cause of security breaches. Attackers exploit known vulnerabilities in outdated software.

How to implement:

  1. AWS Systems Manager Patch Manager: Automate patching across fleets of EC2 instances
  2. Maintenance Windows: Schedule patching during low-traffic periods
  3. Patch Baselines: Define which patches to apply (security, critical, all)
  4. Compliance Reporting: Track patch compliance across your fleet

Detailed Example: Automated Patching with Systems Manager

A company manages 500 EC2 instances and needs to keep them patched. Here's how they use Systems Manager: (1) They install the SSM Agent on all instances (pre-installed on Amazon Linux 2). (2) They create a patch baseline defining which patches to apply: all security patches within 7 days of release. (3) They create a maintenance window: Sundays 2-4 AM. (4) They configure Patch Manager to scan instances daily and apply patches during the maintenance window. (5) Systems Manager automatically patches instances, reboots if necessary, and reports compliance. (6) The security team reviews compliance reports showing 98% of instances are patched. (7) They investigate the 2% non-compliant instances and discover they're offline. (8) Automated patching reduced manual effort and ensured consistent security posture.

Amazon Inspector - Vulnerability Scanning

What it is: Amazon Inspector automatically discovers EC2 instances and container images, scans them for software vulnerabilities and network exposure, and provides risk scores.

Why it matters: Manual vulnerability scanning is time-consuming and error-prone. Inspector automates continuous scanning, ensuring vulnerabilities are detected quickly.

How it works: Inspector scans EC2 instances for CVEs (Common Vulnerabilities and Exposures) by analyzing installed packages. It also performs network reachability analysis to identify exposed services.

Detailed Example: A company enables Inspector for their AWS account. Inspector automatically discovers all EC2 instances and begins scanning. Within hours, Inspector identifies 15 instances with critical CVEs in outdated OpenSSL versions. The security team receives findings with CVE details, affected packages, and remediation steps. They use Systems Manager to patch the vulnerable instances. Inspector rescans and confirms the vulnerabilities are resolved. Continuous scanning ensures new vulnerabilities are detected immediately.


Chapter Summary

What We Covered

  • Edge Security: AWS WAF for application-layer protection, Shield for DDoS mitigation
  • VPC Security: Security groups (stateful), NACLs (stateless), network segmentation
  • Compute Security: EC2 patching, vulnerability scanning with Inspector
  • Defense-in-Depth: Layered security controls from edge to compute

Critical Takeaways

  1. Layer your defenses: Use WAF at the edge, NACLs at the subnet level, security groups at the instance level
  2. Security groups are stateful: Return traffic is automatically allowed - focus on inbound rules
  3. NACLs are stateless: You must explicitly allow return traffic on ephemeral ports (1024-65535)
  4. Reference security groups: Use security group IDs in rules instead of IP addresses for dynamic, scalable security
  5. Automate patching: Use Systems Manager Patch Manager to keep instances updated
  6. Continuous scanning: Enable Inspector for automated vulnerability detection
  7. Explicit deny with NACLs: Use NACLs to block specific IPs or ports that security groups cannot deny

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between security groups and NACLs
  • I understand how to configure WAF rules to protect against OWASP Top 10
  • I know when to use Shield Standard vs Shield Advanced
  • I can design a secure three-tier VPC architecture with proper segmentation
  • I understand stateful vs stateless firewall behavior
  • I can troubleshoot connectivity issues using security groups, NACLs, and VPC Flow Logs
  • I know how to automate EC2 patching with Systems Manager

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-25 (Edge and network security)
  • Domain 3 Bundle 2: Questions 26-50 (Compute security and troubleshooting)
  • Expected score: 70%+ to proceed

Quick Reference Card

Key Services:

  • AWS WAF: Layer 7 firewall, protects against OWASP Top 10
  • AWS Shield: DDoS protection (Standard free, Advanced $3k/month)
  • Security Groups: Stateful, instance-level, implicit deny, allow only
  • NACLs: Stateless, subnet-level, explicit allow/deny, rule order matters
  • Systems Manager: Automated patching, compliance reporting
  • Inspector: Automated vulnerability scanning, CVE detection

Key Concepts:

  • Stateful: Return traffic automatically allowed (security groups)
  • Stateless: Return traffic must be explicitly allowed (NACLs)
  • Defense-in-Depth: Multiple layers of security controls
  • Least Privilege: Only allow necessary traffic, deny everything else

Decision Points:

  • Need layer 7 protection → AWS WAF
  • Need DDoS protection → Shield (Standard for basic, Advanced for enhanced)
  • Need instance-level firewall → Security Groups
  • Need subnet-level firewall → NACLs
  • Need to block specific IPs → NACLs (explicit deny)
  • Need automated patching → Systems Manager Patch Manager
  • Need vulnerability scanning → Amazon Inspector

Next Chapter: Chapter 4 - Identity and Access Management (16% of exam)

Amazon Inspector - Automated Vulnerability Scanning

What it is: Amazon Inspector is an automated security assessment service that continuously scans EC2 instances, container images in ECR, and Lambda functions for software vulnerabilities and network exposure. It identifies CVEs (Common Vulnerabilities and Exposures) and provides prioritized findings with remediation guidance.

Why it exists: Manual vulnerability scanning is time-consuming, inconsistent, and doesn't scale. Applications use hundreds of software packages, each with potential vulnerabilities. New CVEs are discovered daily. Inspector automates continuous scanning, ensuring you're always aware of vulnerabilities in your environment.

Real-world analogy: Inspector is like having a security expert continuously audit your building for weaknesses - checking locks, testing alarms, inspecting windows. Instead of annual audits (manual scanning), you get real-time alerts whenever a new vulnerability is discovered.

How Inspector works (Detailed step-by-step):

  1. Automatic Discovery: Inspector automatically discovers EC2 instances with SSM agent, ECR container images, and Lambda functions in your account. No manual configuration needed.

  2. Continuous Scanning: Inspector continuously scans discovered resources. For EC2, it scans every 24 hours and when packages change. For ECR, it scans on image push and when new CVEs are published.

  3. Package Inventory: Inspector uses SSM agent to collect software package inventory from EC2 instances (RPM, DEB, Python, Node.js packages). For containers, it analyzes image layers.

  4. CVE Matching: Inspector compares package versions against CVE databases (NVD, vendor advisories). It identifies which CVEs affect your specific package versions.

  5. Network Reachability Analysis: Inspector analyzes security groups, NACLs, route tables, and internet gateways to determine if vulnerable services are reachable from the internet.

  6. Risk Scoring: Each finding receives a severity score (Critical, High, Medium, Low, Informational) based on CVSS score and network exposure. Internet-accessible vulnerabilities get higher priority.

  7. Finding Generation: Inspector creates findings in Security Hub and its own console. Each finding includes CVE ID, affected package, remediation guidance (update to version X.Y.Z), and network path analysis.

  8. Suppression Rules: You can create suppression rules to ignore findings for specific CVEs, packages, or resources (e.g., suppress findings for test environments).

  9. Integration: Inspector findings appear in Security Hub, EventBridge, and can trigger automated remediation via Lambda functions.

Detailed Example 1: Responding to Critical CVE

A financial services company uses Inspector to scan their EC2 fleet. Here's what happens when a critical vulnerability is discovered:

Day 1 - 9:00 AM: A critical CVE (CVE-2024-12345) is published affecting OpenSSL 1.1.1k. The vulnerability allows remote code execution.

Day 1 - 9:15 AM: Inspector automatically scans all EC2 instances and identifies 47 instances running the vulnerable OpenSSL version.

Day 1 - 9:20 AM: Inspector generates Critical findings for all 47 instances. Findings include:

  • CVE ID: CVE-2024-12345
  • Affected package: openssl-1.1.1k
  • Severity: Critical (CVSS 9.8)
  • Network exposure: 12 instances are internet-accessible (higher priority)
  • Remediation: Update to openssl-1.1.1l or later

Day 1 - 9:25 AM: Inspector sends findings to Security Hub, which triggers an EventBridge rule.

Day 1 - 9:30 AM: EventBridge invokes a Lambda function that:

  • Creates a high-priority ticket in Jira
  • Sends Slack notification to security team
  • Tags affected instances with "VulnerableOpenSSL"
  • Creates a Systems Manager maintenance window for patching

Day 1 - 10:00 AM: Security team reviews findings and prioritizes the 12 internet-accessible instances.

Day 1 - 2:00 PM: Systems Manager Patch Manager runs on the 12 high-priority instances, updating OpenSSL to 1.1.1l.

Day 1 - 2:30 PM: Inspector rescans the patched instances and closes the findings (vulnerability no longer present).

Day 2 - 10:00 AM: Remaining 35 instances are patched during scheduled maintenance window.

Result: Critical vulnerability identified and remediated within 24 hours. Internet-accessible instances patched within 5 hours. Full audit trail in CloudTrail and Security Hub.

Systems Manager Patch Manager - Automated Patching

What it is: AWS Systems Manager Patch Manager automates the process of patching EC2 instances and on-premises servers with security updates and other patches. It supports Windows, Linux, and macOS operating systems.

Why it exists: Unpatched systems are the #1 cause of security breaches. Manual patching doesn't scale, is error-prone, and often delayed. Patch Manager automates patch deployment, ensures consistency, and provides compliance reporting.

Real-world analogy: Patch Manager is like an automated software update system for your phone, but for servers. Instead of manually updating each server (tedious, forgotten), patches are automatically applied on a schedule you define.

How Patch Manager works (Detailed step-by-step):

  1. Patch Baseline Definition: Create a patch baseline defining which patches to install. AWS provides predefined baselines (e.g., "AWS-DefaultPatchBaseline" for Amazon Linux). Custom baselines can specify patch severity, classification, and approval rules.

  2. Maintenance Window Creation: Define maintenance windows specifying when patching can occur (e.g., "Every Sunday 2-4 AM"). This prevents patching during business hours.

  3. Target Selection: Specify which instances to patch using tags, instance IDs, or resource groups (e.g., all instances tagged "Environment=Production").

  4. Patch Scan: Patch Manager scans instances to identify missing patches. It compares installed packages against the patch baseline.

  5. Patch Installation: During the maintenance window, Patch Manager installs approved patches. It can install patches immediately or stage them for later installation.

  6. Reboot Handling: Patch Manager can automatically reboot instances if required by patches. You can configure reboot behavior (always, never, or only if required).

  7. Compliance Reporting: After patching, Patch Manager reports compliance status. You can see which instances are compliant, which patches are missing, and patch installation history.

  8. Integration with Inspector: Inspector findings can trigger Patch Manager runs to remediate specific vulnerabilities.

Detailed Example 2: Enterprise Patching Strategy

A healthcare organization manages 500 EC2 instances across development, staging, and production environments. They implement a phased patching strategy:

Patch Baseline Configuration:

  • Development: Install all patches immediately (aggressive)
  • Staging: Install Critical and Important patches within 7 days
  • Production: Install Critical patches within 3 days, Important within 14 days

Maintenance Windows:

  • Development: Daily at 2 AM (1-hour window)
  • Staging: Wednesdays at 2 AM (2-hour window)
  • Production: Sundays at 2 AM (4-hour window, staggered by AZ)

Patching Workflow:

Week 1 - Tuesday: Microsoft releases Patch Tuesday updates including a Critical Windows vulnerability.

Week 1 - Wednesday 2 AM: Development instances automatically patched. Patch Manager installs all updates, reboots instances, and reports compliance.

Week 1 - Wednesday 10 AM: QA team tests applications on development instances. No issues found.

Week 2 - Wednesday 2 AM: Staging instances patched with Critical and Important updates. Automated tests run post-patching to verify application functionality.

Week 2 - Thursday: Security team reviews staging patch results. All tests passed.

Week 2 - Sunday 2 AM: Production patching begins. Patch Manager patches instances in us-east-1a first (100 instances), waits 30 minutes, then patches us-east-1b (100 instances), then us-east-1c (100 instances). Staggered approach ensures high availability.

Week 2 - Sunday 6 AM: All production instances patched and compliant. Patch Manager sends SNS notification to security team with compliance report.

Week 2 - Monday: Security team reviews Patch Manager compliance dashboard. 498/500 instances compliant. 2 instances failed patching due to disk space issues. Tickets created for remediation.

Result: Systematic patching with minimal risk. Development tested first, then staging, then production. Staggered production patching maintains availability. Full compliance reporting and audit trail.

Must Know (Critical Facts):

  • EC2 Image Builder automates AMI creation with hardening, patching, and testing. Use it to create golden AMIs rather than manual processes. Supports component-based builds and automated distribution.

  • Amazon Inspector continuously scans for vulnerabilities in EC2 instances, ECR images, and Lambda functions. It automatically discovers resources, scans for CVEs, and prioritizes findings based on network exposure.

  • Inspector findings include remediation guidance specifying which package version to update to. Integrate with Systems Manager Patch Manager for automated remediation.

  • Systems Manager Patch Manager automates patching across EC2 and on-premises servers. Use patch baselines to control which patches are installed and maintenance windows to control when.

  • SSM Agent is required for Systems Manager functionality including Patch Manager, Session Manager, and Inspector scanning. Pre-installed on Amazon Linux, Ubuntu, and Windows AMIs.

  • Instance roles grant permissions to EC2 instances without embedding credentials. Use instance profiles to attach roles. Instances automatically receive temporary credentials that rotate every 6 hours.

  • Secrets Manager stores and rotates secrets like database passwords and API keys. Applications retrieve secrets at runtime rather than hardcoding them. Supports automatic rotation for RDS, Redshift, and DocumentDB.

  • Parameter Store stores configuration data and secrets. Free tier available (unlike Secrets Manager). Supports hierarchical organization and versioning. Use for non-sensitive config and sensitive secrets.

  • CloudWatch agent collects logs and metrics from EC2 instances. Install on instances to send application logs, system logs, and custom metrics to CloudWatch. Essential for security monitoring.

When to use (Comprehensive):

  • Use EC2 Image Builder when: You need to create and maintain hardened AMIs at scale. Automates the build, test, and distribution process. Better than manual AMI creation for consistency and compliance.

  • Use Amazon Inspector when: You need continuous vulnerability scanning and compliance checking. Automatically discovers resources and scans for CVEs. Essential for meeting compliance requirements (PCI-DSS, HIPAA).

  • Use Systems Manager Patch Manager when: You need to automate patching across many instances. Provides compliance reporting and integrates with maintenance windows. Better than manual patching or third-party tools.

  • Use instance roles when: EC2 instances need to access AWS services. Eliminates need for access keys. Credentials automatically rotate. Always prefer roles over access keys for EC2.

  • Use Secrets Manager when: You need automatic secret rotation or integration with RDS/Redshift. Worth the cost ($0.40/secret/month) for automatic rotation and audit trail.

  • Use Parameter Store when: You need to store configuration data or secrets without automatic rotation. Free tier supports 10,000 parameters. Good for non-sensitive config and secrets that don't need rotation.

  • Don't hardcode credentials in AMIs, user data, or application code. Use instance roles, Secrets Manager, or Parameter Store instead. Hardcoded credentials are a major security risk.

  • Don't use long-term access keys for EC2 instances. Use instance roles which provide temporary credentials that automatically rotate. Access keys can be stolen and don't expire.

  • Don't skip vulnerability scanning thinking you're safe because you patch regularly. New vulnerabilities are discovered daily. Inspector provides continuous scanning and prioritization.

Limitations & Constraints:

  • Inspector requires SSM agent for EC2 scanning. Agent must be running and have network connectivity to Systems Manager endpoints. Pre-installed on Amazon Linux 2023 and newer AMIs.

  • Inspector ECR scanning limited to 10,000 images per account per region. For larger image repositories, use multiple accounts or regions.

  • Patch Manager requires SSM agent and instance role with AmazonSSMManagedInstanceCore policy. Instances must be able to reach Systems Manager endpoints (via internet gateway, NAT gateway, or VPC endpoints).

  • Patch Manager reboots may cause downtime if not properly planned. Use maintenance windows during low-traffic periods and stagger patching across availability zones.

  • Image Builder builds can take 30-60 minutes depending on complexity. Plan for build time when creating pipelines. Use caching to speed up subsequent builds.

  • Secrets Manager costs $0.40 per secret per month plus $0.05 per 10,000 API calls. For large numbers of secrets, costs can add up. Consider Parameter Store for cost-sensitive use cases.

💡 Tips for Understanding:

  • Think of AMI hardening as "baking in" security rather than "bolting on" security after launch. Baked-in security is consistent, automated, and scales better.

  • Inspector findings are prioritized by risk (severity + network exposure). Focus on Critical/High findings for internet-accessible resources first. Low severity findings on internal resources can wait.

  • Patch Manager compliance is binary - either compliant (all approved patches installed) or non-compliant (missing patches). Use compliance reports to track patching progress and identify problem instances.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking Inspector only scans when you manually trigger it

    • Why it's wrong: Inspector continuously scans. EC2 instances are scanned every 24 hours and when packages change. ECR images are scanned on push and when new CVEs are published.
    • Correct understanding: Inspector is "always on" - you don't need to schedule scans. It automatically discovers resources and scans them continuously.
  • Mistake 2: Believing patching with Patch Manager is immediate

    • Why it's wrong: Patch Manager respects maintenance windows. Patches are installed only during defined maintenance windows, not immediately when available.
    • Correct understanding: Patch Manager provides controlled, scheduled patching. You define when patching occurs via maintenance windows. For urgent patches, you can run Patch Manager on-demand outside maintenance windows.
  • Mistake 3: Assuming instance roles are the same as IAM roles

    • Why it's wrong: Instance roles are IAM roles attached to EC2 instances via instance profiles. The instance profile is the container that passes the role to the instance.
    • Correct understanding: You create an IAM role, then create an instance profile that references the role, then attach the instance profile to the EC2 instance. The instance receives temporary credentials from the role.

🔗 Connections to Other Topics:

  • Relates to Security Hub (Domain 1) because: Inspector findings are automatically sent to Security Hub for centralized security posture management. Security Hub aggregates findings from Inspector, GuardDuty, and other services.

  • Builds on IAM Roles (Domain 4) by: Using instance roles to grant EC2 instances permissions to access other AWS services without embedding credentials. Instance roles use temporary credentials that automatically rotate.

  • Often used with CloudWatch Logs (Domain 2) to: Collect and analyze logs from EC2 instances. CloudWatch agent sends logs to CloudWatch Logs for centralized monitoring and alerting.


Section 4: Network Troubleshooting

Introduction

The problem: Network connectivity issues are common in AWS environments. Applications can't reach databases, users can't access web applications, or services can't communicate across VPCs. Without systematic troubleshooting, you waste time guessing at the root cause.

The solution: AWS provides multiple tools for network troubleshooting including VPC Flow Logs, VPC Reachability Analyzer, Traffic Mirroring, and CloudWatch metrics. Combined with understanding of TCP/IP fundamentals and AWS networking concepts, these tools enable rapid diagnosis of connectivity issues.

Why it's tested: The exam includes troubleshooting scenarios where you must diagnose why network traffic is blocked. You need to understand how to use VPC Flow Logs to identify rejected connections, how to analyze security group and NACL rules, and how to determine the root cause of connectivity failures.

Core Concepts

VPC Flow Logs - Network Traffic Analysis

What it is: VPC Flow Logs capture information about IP traffic going to and from network interfaces in your VPC. They record source/destination IPs, ports, protocols, packet counts, byte counts, and accept/reject decisions.

Why it exists: Without visibility into network traffic, you can't diagnose connectivity issues, detect security threats, or understand traffic patterns. Flow Logs provide a record of all network activity for troubleshooting and security analysis.

Real-world analogy: VPC Flow Logs are like security camera footage for your network. Just as cameras record who enters and exits a building, Flow Logs record what traffic enters and exits your VPC, which helps investigate incidents and identify problems.

How Flow Logs work (Detailed step-by-step):

  1. Flow Log Creation: You create a Flow Log for a VPC, subnet, or network interface. Specify the destination (CloudWatch Logs or S3) and filter (ALL traffic, ACCEPT only, or REJECT only).

  2. Traffic Capture: As packets flow through the network interface, the VPC infrastructure captures metadata about each flow (a flow is a sequence of packets with the same 5-tuple: source IP, destination IP, source port, destination port, protocol).

  3. Aggregation: Flow records are aggregated over a capture window (default 10 minutes, configurable to 1 minute). Multiple packets in the same flow are combined into a single flow record.

  4. Flow Record Generation: For each flow, a flow record is created containing: account ID, interface ID, source IP, destination IP, source port, destination port, protocol, packets, bytes, start time, end time, action (ACCEPT or REJECT), log status.

  5. Delivery: Flow records are delivered to the specified destination (CloudWatch Logs or S3). Delivery typically occurs within 5-15 minutes of the capture window ending.

  6. Analysis: You query Flow Logs using CloudWatch Logs Insights or Athena (for S3) to identify rejected connections, top talkers, traffic patterns, and security threats.

Detailed Example 1: Diagnosing Rejected Database Connection

A web application can't connect to an RDS database. The application logs show "Connection timeout" errors. Here's how to use Flow Logs to diagnose:

Step 1 - Enable Flow Logs: Create a Flow Log for the application subnet with filter "REJECT" to capture only rejected traffic. Destination: CloudWatch Logs.

Step 2 - Reproduce Issue: Trigger the application to attempt database connection. Wait 15 minutes for Flow Logs to be delivered.

Step 3 - Query Flow Logs: Use CloudWatch Logs Insights with query:

fields @timestamp, srcAddr, dstAddr, dstPort, action
| filter dstPort = 3306 and action = "REJECT"
| sort @timestamp desc

Step 4 - Analyze Results: Flow Log shows:

  • Source: 10.0.1.50 (application instance)
  • Destination: 10.0.2.100 (RDS instance)
  • Port: 3306 (MySQL)
  • Action: REJECT

Step 5 - Identify Root Cause: The REJECT indicates traffic was blocked by security group or NACL. Check security group on RDS instance - it only allows port 3306 from 10.0.1.0/25, but application is in 10.0.1.128/25 (different subnet). Security group rule is too restrictive.

Step 6 - Fix: Update RDS security group to allow port 3306 from entire VPC CIDR (10.0.0.0/16) or specifically from application subnet (10.0.1.128/25).

Step 7 - Verify: Application successfully connects to database. Flow Logs now show ACCEPT for port 3306 traffic.

Result: Flow Logs identified that traffic was rejected, which narrowed the problem to security groups or NACLs. Checking security group rules revealed the misconfiguration. Total troubleshooting time: 20 minutes instead of hours of guessing.


Chapter Summary

What We Covered

  • Edge Security: AWS WAF, Shield, CloudFront security features, and layered defense strategies
  • Network Security: VPC security groups, NACLs, Network Firewall, VPC endpoints, and network segmentation
  • Compute Security: EC2 hardening, AMI creation, vulnerability scanning with Inspector, patching with Systems Manager
  • Network Troubleshooting: VPC Flow Logs, Reachability Analyzer, Traffic Mirroring, and systematic troubleshooting approaches

Critical Takeaways

  1. Layered Defense: Combine multiple security controls (WAF + Shield + CloudFront + ALB + Security Groups) for defense in depth. No single control is sufficient.

  2. Security Groups are Stateful, NACLs are Stateless: Security groups automatically allow return traffic. NACLs require explicit rules for both directions. Use security groups for most use cases.

  3. Inspector Continuously Scans: Inspector automatically discovers EC2 instances and ECR images, then continuously scans for vulnerabilities. No manual triggering needed.

  4. VPC Flow Logs Show ACCEPT/REJECT: Use Flow Logs to diagnose connectivity issues. REJECT indicates security group or NACL blocked traffic. ACCEPT means traffic was allowed.

  5. Patch Manager Respects Maintenance Windows: Patching occurs during defined maintenance windows, not immediately. For urgent patches, run Patch Manager on-demand.

  6. Instance Roles Use Temporary Credentials: EC2 instances receive temporary credentials from IAM roles via instance profiles. Credentials automatically rotate every 6 hours.

  7. Network Firewall Provides Stateful Inspection: Unlike NACLs (stateless), Network Firewall performs deep packet inspection with stateful rules. Use for advanced filtering and IDS/IPS.

  8. VPC Endpoints Keep Traffic Private: Interface and Gateway endpoints allow access to AWS services without traversing the internet. Improves security and reduces data transfer costs.

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between AWS WAF and AWS Shield
  • I can design a layered defense architecture using multiple edge services
  • I understand when to use security groups vs. NACLs
  • I can explain how VPC endpoints improve security
  • I know how to create hardened AMIs using EC2 Image Builder
  • I can interpret Inspector findings and prioritize remediation
  • I understand how Patch Manager works with maintenance windows
  • I can use VPC Flow Logs to diagnose connectivity issues
  • I know the difference between stateful and stateless firewalls
  • I can explain how instance roles provide credentials to EC2 instances

If you answered "no" to any of these, review the relevant section before proceeding.

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-50 (Infrastructure Security fundamentals)
  • Domain 3 Bundle 2: Questions 51-100 (Advanced infrastructure security)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections on services you got wrong
  • Focus on understanding WHEN to use each security control
  • Practice distinguishing between similar services (Security Groups vs. NACLs, WAF vs. Shield)
  • Review troubleshooting methodologies for network connectivity issues

Quick Reference Card

Edge Security Services:

  • AWS WAF: Layer 7 web application firewall (SQL injection, XSS, rate limiting)
  • AWS Shield Standard: Free DDoS protection (Layer 3/4)
  • AWS Shield Advanced: Enhanced DDoS protection + DDoS Response Team + cost protection
  • CloudFront: CDN with geo-blocking, signed URLs, field-level encryption

Network Security:

  • Security Groups: Stateful, instance-level, allow rules only, default deny
  • NACLs: Stateless, subnet-level, allow and deny rules, numbered rules (lowest first)
  • Network Firewall: Stateful inspection, IDS/IPS, domain filtering, Suricata rules
  • VPC Endpoints: Private connectivity to AWS services (Interface and Gateway types)

Compute Security:

  • EC2 Image Builder: Automated AMI creation with hardening and testing
  • Amazon Inspector: Continuous vulnerability scanning (EC2 and ECR)
  • Systems Manager Patch Manager: Automated patching with maintenance windows
  • Instance Roles: IAM roles for EC2 with temporary credentials

Troubleshooting Tools:

  • VPC Flow Logs: Network traffic metadata (5-tuple + action)
  • VPC Reachability Analyzer: Path analysis without sending packets
  • Traffic Mirroring: Copy network traffic for deep inspection
  • CloudWatch Metrics: Network performance and error metrics

Decision Points:

  • Web application attacks → AWS WAF
  • DDoS attacks → AWS Shield (Standard for basic, Advanced for critical workloads)
  • Instance-level firewall → Security Groups
  • Subnet-level firewall → NACLs
  • Advanced filtering/IDS → Network Firewall
  • Private AWS service access → VPC Endpoints
  • Vulnerability scanning → Amazon Inspector
  • Automated patching → Systems Manager Patch Manager
  • Network troubleshooting → VPC Flow Logs
  • Path analysis → VPC Reachability Analyzer

Chapter 3 Complete

Next Chapter: 05_domain4_iam - Identity and Access Management (16% of exam)

AWS Network Firewall - Advanced Network Protection

What it is: AWS Network Firewall is a managed network firewall service that provides stateful inspection, intrusion detection and prevention (IDS/IPS), and domain filtering for your VPCs. It uses Suricata-compatible rules for deep packet inspection.

Why it exists: While security groups and NACLs provide basic filtering, they cannot inspect packet payloads, detect malware signatures, or filter based on domain names. Network Firewall fills this gap by providing advanced threat protection at the network level.

Real-world analogy: If security groups are door locks and NACLs are security checkpoints, Network Firewall is a sophisticated security system with cameras, motion detectors, and AI-powered threat detection that analyzes everything happening in your building.

How it works (Detailed step-by-step):

  1. Firewall Deployment: You deploy Network Firewall endpoints in dedicated firewall subnets within your VPC.
  2. Traffic Routing: You configure route tables to direct traffic through the firewall endpoints for inspection.
  3. Rule Evaluation: Network Firewall evaluates traffic against firewall policies containing stateless and stateful rule groups.
  4. Stateless Rules: Evaluated first, these rules perform fast packet filtering based on 5-tuple (source IP, destination IP, source port, destination port, protocol).
  5. Stateful Rules: If traffic passes stateless rules, stateful rules perform deep packet inspection using Suricata-compatible rules.
  6. Domain Filtering: Network Firewall can filter traffic based on domain names, blocking access to malicious or unauthorized domains.
  7. IDS/IPS: Suricata rules detect known attack signatures and can drop malicious traffic.
  8. Logging: Network Firewall logs all traffic (allowed and blocked) to CloudWatch Logs, S3, or Kinesis Data Firehose.
  9. Action: Based on rule matches, Network Firewall allows, drops, or alerts on traffic.

📊 AWS Network Firewall Architecture Diagram:

graph TB
    subgraph "VPC: 10.0.0.0/16"
        subgraph "Firewall Subnet: 10.0.1.0/24"
            NFW[Network Firewall<br/>Endpoint]
        end
        
        subgraph "Public Subnet: 10.0.2.0/24"
            IGW[Internet Gateway]
            NAT[NAT Gateway]
        end
        
        subgraph "Private Subnet: 10.0.3.0/24"
            EC2_1[EC2 Instance 1]
            EC2_2[EC2 Instance 2]
        end
        
        subgraph "Firewall Policy"
            Stateless[Stateless Rules<br/>Fast 5-tuple filtering]
            Stateful[Stateful Rules<br/>Deep packet inspection]
            Domain[Domain Filtering<br/>Block malicious domains]
            IDS[IDS/IPS Rules<br/>Suricata signatures]
        end
    end
    
    Internet[Internet]
    Logs[CloudWatch Logs<br/>S3 / Kinesis]
    
    Internet --> IGW
    IGW --> NFW
    NFW --> NAT
    NAT --> EC2_1
    NAT --> EC2_2
    
    EC2_1 --> NFW
    EC2_2 --> NFW
    NFW --> IGW
    
    Stateless -.-> NFW
    Stateful -.-> NFW
    Domain -.-> NFW
    IDS -.-> NFW
    
    NFW -->|Logs| Logs
    
    style NFW fill:#c8e6c9
    style Stateless fill:#e1f5fe
    style Stateful fill:#fff3e0
    style Domain fill:#f3e5f5
    style IDS fill:#ffebee

See: diagrams/04_domain3_network_firewall_architecture.mmd

Diagram Explanation (Detailed):

The diagram shows AWS Network Firewall deployed in a centralized inspection architecture. The Network Firewall endpoint is deployed in a dedicated firewall subnet (10.0.1.0/24). All traffic entering and leaving the VPC is routed through the firewall endpoint for inspection. Internet-bound traffic from EC2 instances flows through the firewall endpoint, then to the NAT Gateway, and finally to the Internet Gateway. Inbound traffic from the internet flows through the Internet Gateway, then the firewall endpoint, before reaching EC2 instances. The firewall policy contains four types of rules: (1) Stateless Rules perform fast 5-tuple filtering for basic allow/deny decisions. (2) Stateful Rules perform deep packet inspection to detect application-layer threats. (3) Domain Filtering blocks access to malicious or unauthorized domains by inspecting DNS queries and HTTP/HTTPS requests. (4) IDS/IPS Rules use Suricata signatures to detect and block known attack patterns like malware, exploits, and command-and-control traffic. All traffic (allowed and blocked) is logged to CloudWatch Logs, S3, or Kinesis Data Firehose for security analysis. This architecture provides centralized, advanced threat protection for the entire VPC.

Detailed Example 1: Blocking Malware Command-and-Control Traffic

A security team wants to prevent compromised instances from communicating with malware command-and-control (C2) servers. Here's how they use Network Firewall: (1) They deploy Network Firewall in their VPC and configure route tables to direct all outbound traffic through the firewall. (2) They create a stateful rule group using Suricata rules from threat intelligence feeds that identify known C2 domains and IP addresses. (3) They configure the rule action to DROP and ALERT. (4) An EC2 instance is compromised by malware that attempts to connect to a C2 server at malicious-c2.example.com. (5) Network Firewall intercepts the DNS query and HTTP connection attempt. (6) The stateful rule matches the C2 domain and drops the connection. (7) Network Firewall logs the blocked connection with details: source IP, destination domain, Suricata rule ID, and timestamp. (8) The security team receives an alert and investigates the compromised instance. (9) They isolate the instance and perform forensic analysis. Network Firewall prevented the malware from receiving commands or exfiltrating data, containing the breach.

Detailed Example 2: Implementing Egress Filtering for Compliance

A financial services company must comply with regulations requiring egress filtering to prevent data exfiltration. Here's how they use Network Firewall: (1) They deploy Network Firewall in all VPCs containing sensitive data. (2) They create a domain allow list containing only approved external domains: their banking partners, payment processors, and regulatory reporting systems. (3) They configure a stateful rule group with domain filtering: ALLOW traffic to approved domains, DROP all other outbound traffic. (4) They enable logging to S3 for compliance auditing. (5) A developer accidentally attempts to upload data to a personal cloud storage service at personal-cloud.example.com. (6) Network Firewall blocks the connection because the domain is not on the allow list. (7) The blocked attempt is logged with full details. (8) The security team reviews logs and identifies the policy violation. (9) They provide additional training to the developer. Network Firewall enforced egress filtering, preventing unauthorized data exfiltration and maintaining compliance.

Detailed Example 3: Detecting and Blocking SQL Injection Attacks

A company wants to protect their web application from SQL injection attacks at the network level. Here's how they use Network Firewall: (1) They deploy Network Firewall in front of their Application Load Balancer. (2) They create a stateful rule group with Suricata rules that detect SQL injection patterns in HTTP requests. (3) Example Suricata rule: alert http any any -> any any (msg:"SQL Injection Attempt"; content:"' OR '1'='1"; http_uri; sid:1000001; rev:1;). (4) They configure the rule action to DROP and ALERT. (5) An attacker sends a malicious HTTP request: GET /search?query=' OR '1'='1 HTTP/1.1. (6) Network Firewall's stateful engine inspects the HTTP request payload. (7) The Suricata rule matches the SQL injection pattern in the query parameter. (8) Network Firewall drops the request and logs the attack with details: source IP, HTTP method, URI, matched rule, and payload. (9) The security team receives an alert and adds the attacker's IP to a block list. (10) The SQL injection attack never reaches the application servers. Network Firewall provided deep packet inspection to detect and block application-layer attacks.

Must Know (Critical Facts):

  • Network Firewall uses Suricata-compatible rules for IDS/IPS functionality
  • Stateless rules are evaluated before stateful rules for performance optimization
  • Domain filtering works by inspecting DNS queries and SNI (Server Name Indication) in TLS handshakes
  • Network Firewall can be deployed in centralized (hub VPC) or distributed (each VPC) architectures
  • Firewall endpoints are deployed in dedicated subnets with route table modifications to direct traffic through them
  • Network Firewall supports both allow lists (permit only approved traffic) and deny lists (block known bad traffic)
  • Logging can be sent to CloudWatch Logs, S3, or Kinesis Data Firehose for analysis and compliance

When to use (Comprehensive):

  • ✅ Use when: You need deep packet inspection beyond what security groups and NACLs provide
  • ✅ Use when: You need to filter traffic based on domain names (e.g., block access to malicious domains)
  • ✅ Use when: You need IDS/IPS capabilities to detect and block known attack signatures
  • ✅ Use when: You need to inspect encrypted traffic using TLS/SSL inspection
  • ✅ Use when: Compliance requirements mandate egress filtering and detailed traffic logging
  • ✅ Use when: You need centralized firewall management across multiple VPCs
  • ❌ Don't use when: Simple 5-tuple filtering is sufficient (use security groups or NACLs instead for lower cost)
  • ❌ Don't use when: You only need to protect web applications (use AWS WAF instead for application-layer protection)

Limitations & Constraints:

  • Network Firewall endpoints have throughput limits (scale by adding more endpoints)
  • Suricata rules must be carefully tuned to avoid false positives
  • TLS/SSL inspection requires certificate management and can impact performance
  • Firewall endpoints are deployed per Availability Zone (plan for high availability)
  • Route table modifications are required to direct traffic through firewall endpoints

💡 Tips for Understanding:

  • Think of Network Firewall as a "next-generation firewall" (NGFW) in the cloud
  • Stateless rules are like NACLs (fast, simple), stateful rules are like IDS/IPS (deep, complex)
  • Domain filtering is powerful for blocking malware C2 and data exfiltration
  • Use managed rule groups from AWS and partners to get started quickly
  • Always test firewall rules in a non-production environment first

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Deploying Network Firewall without modifying route tables
    • Why it's wrong: Traffic won't flow through the firewall if routes aren't configured
    • Correct understanding: You must update route tables to direct traffic to firewall endpoints
  • Mistake 2: Using only stateless rules and expecting deep packet inspection
    • Why it's wrong: Stateless rules only inspect packet headers, not payloads
    • Correct understanding: Use stateful rules with Suricata for deep packet inspection
  • Mistake 3: Forgetting to allow return traffic in stateful rules
    • Why it's wrong: Stateful rules track connections, but you still need rules for both directions
    • Correct understanding: Create rules for both inbound and outbound traffic flows

🔗 Connections to Other Topics:

  • Relates to VPC Flow Logs because: Network Firewall logs complement Flow Logs with deep packet inspection details
  • Builds on Security Groups and NACLs by: Providing advanced filtering beyond basic 5-tuple rules
  • Often used with AWS WAF to: Create defense-in-depth (WAF for application layer, Network Firewall for network layer)
  • Integrates with AWS Firewall Manager to: Centrally manage firewall policies across multiple accounts

Troubleshooting Common Issues:

  • Issue 1: Traffic not flowing through Network Firewall
    • Problem: Route tables not configured correctly
    • Solution: Verify route tables direct traffic to firewall endpoints (0.0.0.0/0 → firewall endpoint)
  • Issue 2: Legitimate traffic being blocked
    • Problem: Overly restrictive Suricata rules causing false positives
    • Solution: Review firewall logs, identify false positives, tune rules or add exceptions
  • Issue 3: High latency after deploying Network Firewall
    • Problem: Insufficient firewall endpoint capacity
    • Solution: Deploy additional firewall endpoints or optimize rule complexity

VPC Endpoints - Private Connectivity to AWS Services

What it is: VPC endpoints enable private connectivity between your VPC and AWS services without using the internet, NAT devices, VPN connections, or AWS Direct Connect. There are two types: Interface endpoints (powered by AWS PrivateLink) and Gateway endpoints.

Why it exists: By default, traffic to AWS services like S3 and DynamoDB goes over the internet, exposing it to potential interception and requiring internet connectivity. VPC endpoints keep traffic within the AWS network, improving security and reducing data transfer costs.

Real-world analogy: VPC endpoints are like private tunnels between your building and a service provider's building. Instead of going through public streets (the internet), you have a direct, private connection.

How it works (Detailed step-by-step):

Gateway Endpoints (S3 and DynamoDB):

  1. Endpoint Creation: You create a gateway endpoint for S3 or DynamoDB in your VPC.
  2. Route Table Update: AWS automatically adds routes to your route tables directing traffic to the endpoint.
  3. Traffic Routing: When an EC2 instance accesses S3 or DynamoDB, traffic is routed through the gateway endpoint instead of the internet.
  4. Private Communication: Traffic stays within the AWS network, never traversing the internet.
  5. No Additional Charges: Gateway endpoints are free (you only pay for data transfer).

Interface Endpoints (Most AWS Services):

  1. Endpoint Creation: You create an interface endpoint for a service (e.g., Secrets Manager, Systems Manager).
  2. ENI Provisioning: AWS provisions elastic network interfaces (ENIs) in your subnets with private IP addresses.
  3. DNS Resolution: The service's public DNS name resolves to the private IP addresses of the ENIs.
  4. Traffic Routing: When an EC2 instance accesses the service, traffic is routed to the ENI in the same VPC.
  5. Private Communication: Traffic stays within the VPC, never leaving the AWS network.
  6. Security Groups: You can apply security groups to interface endpoints to control access.

📊 VPC Endpoint Types Diagram:

graph TB
    subgraph "VPC: 10.0.0.0/16"
        subgraph "Private Subnet: 10.0.1.0/24"
            EC2[EC2 Instance<br/>10.0.1.10]
        end
        
        subgraph "Gateway Endpoint"
            GW_S3[Gateway Endpoint<br/>for S3]
            GW_DDB[Gateway Endpoint<br/>for DynamoDB]
        end
        
        subgraph "Interface Endpoints"
            INT_SM[Interface Endpoint<br/>Secrets Manager<br/>10.0.1.20]
            INT_SSM[Interface Endpoint<br/>Systems Manager<br/>10.0.1.21]
        end
        
        RT[Route Table<br/>pl-xxx (S3) → vpce-xxx<br/>pl-yyy (DDB) → vpce-yyy]
    end
    
    S3[Amazon S3<br/>AWS Network]
    DDB[DynamoDB<br/>AWS Network]
    SM[Secrets Manager<br/>AWS Network]
    SSM[Systems Manager<br/>AWS Network]
    
    EC2 -->|Private| GW_S3
    EC2 -->|Private| GW_DDB
    EC2 -->|Private| INT_SM
    EC2 -->|Private| INT_SSM
    
    GW_S3 -.->|AWS Network| S3
    GW_DDB -.->|AWS Network| DDB
    INT_SM -.->|AWS Network| SM
    INT_SSM -.->|AWS Network| SSM
    
    RT -.-> GW_S3
    RT -.-> GW_DDB
    
    style GW_S3 fill:#c8e6c9
    style GW_DDB fill:#c8e6c9
    style INT_SM fill:#e1f5fe
    style INT_SSM fill:#e1f5fe
    style EC2 fill:#fff3e0

See: diagrams/04_domain3_vpc_endpoint_types.mmd

Diagram Explanation (Detailed):

The diagram shows both types of VPC endpoints in a single VPC. The EC2 instance (10.0.1.10) in the private subnet can access AWS services privately without internet connectivity. Gateway endpoints for S3 and DynamoDB are configured with route table entries that direct traffic destined for these services (identified by prefix lists pl-xxx and pl-yyy) to the gateway endpoints (vpce-xxx and vpce-yyy). When the EC2 instance accesses S3 or DynamoDB, the route table directs traffic to the gateway endpoint, which forwards it through the AWS network. Interface endpoints for Secrets Manager and Systems Manager are provisioned as elastic network interfaces (ENIs) with private IP addresses (10.0.1.20 and 10.0.1.21) in the same subnet as the EC2 instance. When the EC2 instance accesses these services, DNS resolution returns the private IP addresses of the interface endpoints, and traffic flows directly to the ENIs within the VPC. All traffic stays within the AWS network, improving security by eliminating internet exposure and reducing data transfer costs. Security groups can be applied to interface endpoints to control which resources can access them.

Detailed Example 1: Securing S3 Access with Gateway Endpoints

A company wants to ensure EC2 instances can access S3 without internet connectivity. Here's how they use gateway endpoints: (1) They have EC2 instances in private subnets with no internet access (no NAT Gateway). (2) They create a gateway endpoint for S3 in their VPC. (3) They associate the endpoint with the route tables for the private subnets. (4) AWS automatically adds a route: pl-xxxxx (S3 prefix list) → vpce-xxxxx (gateway endpoint). (5) An EC2 instance runs: aws s3 cp file.txt s3://my-bucket/. (6) The route table directs S3 traffic to the gateway endpoint instead of the internet. (7) Traffic flows through the AWS network to S3, never leaving AWS infrastructure. (8) The S3 upload completes successfully without internet connectivity. (9) They configure an S3 bucket policy to only allow access from their VPC endpoint: "Condition": {"StringNotEquals": {"aws:SourceVpce": "vpce-xxxxx"}}. (10) Attempts to access the bucket from the internet are denied. Gateway endpoints provided secure, private S3 access without internet exposure.

Detailed Example 2: Using Interface Endpoints for Secrets Manager

A company wants to retrieve secrets from Secrets Manager without internet connectivity. Here's how they use interface endpoints: (1) They have Lambda functions in private subnets with no internet access. (2) They create an interface endpoint for Secrets Manager in their VPC. (3) AWS provisions ENIs with private IP addresses in their subnets. (4) They enable private DNS for the endpoint, so secretsmanager.us-east-1.amazonaws.com resolves to the private IPs. (5) A Lambda function runs: boto3.client('secretsmanager').get_secret_value(SecretId='db-password'). (6) DNS resolution returns the private IP of the interface endpoint (e.g., 10.0.1.20). (7) The Lambda function connects to the interface endpoint within the VPC. (8) The endpoint forwards the request to Secrets Manager through the AWS network. (9) The secret is retrieved and returned to the Lambda function. (10) All traffic stayed within the VPC, never traversing the internet. Interface endpoints enabled private access to Secrets Manager from isolated subnets.

Detailed Example 3: Enforcing VPC Endpoint Usage with IAM Policies

A security team wants to ensure all S3 access goes through VPC endpoints, not the internet. Here's how they enforce this: (1) They create gateway endpoints for S3 in all VPCs. (2) They create an IAM policy that denies S3 access unless it comes from a VPC endpoint: {"Effect": "Deny", "Action": "s3:*", "Resource": "*", "Condition": {"StringNotEquals": {"aws:SourceVpce": ["vpce-111", "vpce-222"]}}}. (3) They attach this policy to all IAM roles used by EC2 instances. (4) An EC2 instance in a VPC with a gateway endpoint accesses S3 successfully because traffic goes through the endpoint. (5) An EC2 instance in a VPC without a gateway endpoint attempts to access S3 via the internet. (6) The IAM policy denies the request because aws:SourceVpce doesn't match the allowed endpoints. (7) The access is blocked, and CloudTrail logs the denied request. (8) The security team identifies the non-compliant VPC and creates a gateway endpoint. IAM policies enforced VPC endpoint usage, preventing internet-based S3 access.

Must Know (Critical Facts):

  • Gateway endpoints are free and support only S3 and DynamoDB
  • Interface endpoints cost money (per hour + data processed) and support most AWS services
  • Gateway endpoints use route tables, interface endpoints use ENIs and DNS
  • VPC endpoint policies can restrict which resources can be accessed through the endpoint
  • Interface endpoints can be accessed from on-premises via VPN or Direct Connect
  • Gateway endpoints cannot be accessed from on-premises (VPC-only)
  • Private DNS for interface endpoints makes them transparent to applications (no code changes needed)

When to use (Comprehensive):

  • ✅ Use Gateway Endpoints when: Accessing S3 or DynamoDB from private subnets without internet connectivity
  • ✅ Use Interface Endpoints when: Accessing other AWS services (Secrets Manager, Systems Manager, etc.) from private subnets
  • ✅ Use when: You want to reduce data transfer costs by keeping traffic within AWS network
  • ✅ Use when: Compliance requirements prohibit internet connectivity for sensitive workloads
  • ✅ Use when: You want to enforce that all access to a service goes through your VPC (using endpoint policies)
  • ❌ Don't use when: Your instances already have internet connectivity and cost is not a concern
  • ❌ Don't use when: You need to access services not supported by VPC endpoints

Section 3: Compute Security - Securing EC2 and Containers

Introduction

The problem: Compute workloads (EC2 instances, containers, Lambda functions) are prime targets for attackers. Unpatched vulnerabilities, misconfigured permissions, and insecure secrets management can lead to compromise. Without proper security controls, a single compromised instance can become a foothold for lateral movement.

The solution: AWS provides multiple layers of compute security: hardened AMIs, automated patching, vulnerability scanning, secure secrets management, and least-privilege IAM roles. Together, these controls create defense-in-depth for compute workloads.

Why it's tested: Compute security is fundamental to AWS security. The exam tests your ability to secure EC2 instances, implement automated patching, scan for vulnerabilities, manage secrets securely, and apply least-privilege principles to compute workloads.

Core Concepts

EC2 Image Builder - Automated AMI Creation and Hardening

What it is: EC2 Image Builder is a fully managed service that automates the creation, maintenance, validation, and distribution of secure AMIs. It applies security hardening, installs software, runs tests, and distributes AMIs across regions and accounts.

Why it exists: Manually creating and maintaining AMIs is time-consuming and error-prone. Organizations need a consistent, automated way to build hardened AMIs with security patches, compliance configurations, and validated software installations.

Real-world analogy: EC2 Image Builder is like an automated factory assembly line for building secure server images. Just as a factory follows a precise process to build products consistently, Image Builder follows a pipeline to build secure AMIs.

How it works (Detailed step-by-step):

  1. Pipeline Definition: You define an image pipeline specifying the base AMI, components to install, tests to run, and distribution settings.
  2. Component Selection: You select components (scripts) to install software, apply security hardening (CIS benchmarks), and configure the OS.
  3. Build Execution: Image Builder launches a temporary EC2 instance from the base AMI.
  4. Component Application: Image Builder applies components in order: install software, apply patches, configure security settings.
  5. Testing: Image Builder runs test components to validate the image (e.g., verify software installed, check security configurations).
  6. AMI Creation: If tests pass, Image Builder creates an AMI from the instance.
  7. Distribution: Image Builder distributes the AMI to specified regions and accounts.
  8. Cleanup: Image Builder terminates the temporary instance and cleans up resources.
  9. Scheduling: You can schedule pipelines to run automatically (e.g., weekly) to incorporate new patches.

📊 EC2 Image Builder Pipeline Diagram:

graph TB
    subgraph "Image Builder Pipeline"
        Base[Base AMI<br/>Amazon Linux 2]
        
        subgraph "Build Phase"
            Instance[Temporary EC2<br/>Instance]
            Comp1[Component 1:<br/>Install Software]
            Comp2[Component 2:<br/>Apply CIS Hardening]
            Comp3[Component 3:<br/>Install Security Agents]
        end
        
        subgraph "Test Phase"
            Test1[Test 1:<br/>Verify Software]
            Test2[Test 2:<br/>Security Scan]
        end
        
        subgraph "Distribution"
            AMI[Golden AMI<br/>Hardened & Tested]
            Region1[us-east-1]
            Region2[us-west-2]
            Account2[Account 123456]
        end
    end
    
    Schedule[Scheduled Trigger<br/>Weekly]
    
    Schedule --> Base
    Base --> Instance
    Instance --> Comp1
    Comp1 --> Comp2
    Comp2 --> Comp3
    Comp3 --> Test1
    Test1 --> Test2
    Test2 -->|Pass| AMI
    Test2 -.->|Fail| Cleanup[Cleanup & Alert]
    
    AMI --> Region1
    AMI --> Region2
    AMI --> Account2
    
    style AMI fill:#c8e6c9
    style Test2 fill:#e1f5fe
    style Cleanup fill:#ffebee

See: diagrams/04_domain3_ec2_image_builder_pipeline.mmd

Diagram Explanation (Detailed):

The diagram shows an EC2 Image Builder pipeline that automates the creation of hardened AMIs. The pipeline starts with a base AMI (Amazon Linux 2) and is triggered on a weekly schedule to incorporate new security patches. Image Builder launches a temporary EC2 instance from the base AMI and enters the build phase. In the build phase, components are applied sequentially: Component 1 installs required software (e.g., web server, monitoring agents), Component 2 applies CIS hardening benchmarks (disable unnecessary services, configure secure defaults), and Component 3 installs security agents (antivirus, EDR). After the build phase, the test phase begins. Test 1 verifies that software was installed correctly and is functioning. Test 2 runs a security scan to ensure hardening was applied and no vulnerabilities exist. If tests pass, Image Builder creates a golden AMI from the instance. The AMI is then distributed to multiple regions (us-east-1, us-west-2) and shared with other accounts (Account 123456) for use across the organization. If tests fail, Image Builder cleans up resources and sends an alert. This automated pipeline ensures consistent, secure AMIs are available organization-wide without manual intervention.

Detailed Example 1: Building CIS-Hardened AMIs

A financial services company must comply with CIS benchmarks for all EC2 instances. Here's how they use EC2 Image Builder: (1) They create an image pipeline with Amazon Linux 2 as the base AMI. (2) They add the AWS-provided "CIS Amazon Linux 2 Benchmark Level 1" component, which applies 100+ security configurations. (3) They add custom components to install their monitoring agents and configure logging. (4) They add a test component that runs an automated CIS compliance scan using Amazon Inspector. (5) They schedule the pipeline to run weekly to incorporate new patches. (6) The pipeline executes: launches instance, applies CIS hardening, installs agents, runs compliance scan. (7) The compliance scan passes, confirming the AMI meets CIS Level 1 requirements. (8) Image Builder creates the AMI and distributes it to all regions. (9) The company updates their Auto Scaling groups to use the new hardened AMI. (10) All new EC2 instances are now CIS-compliant by default. EC2 Image Builder automated the creation of compliant AMIs, reducing manual effort and ensuring consistency.

Detailed Example 2: Automated Patching with Image Builder

A company wants to ensure all AMIs include the latest security patches. Here's how they use EC2 Image Builder: (1) They create an image pipeline scheduled to run every Sunday at 2 AM. (2) They use the latest Amazon Linux 2 AMI as the base (which includes recent patches). (3) They add a component that runs yum update -y to install any additional patches released since the base AMI. (4) They add a test component that verifies critical services start correctly after patching. (5) The pipeline runs automatically every week. (6) If patches are available, they're installed and tested. (7) A new AMI is created with the latest patches. (8) The company's CI/CD pipeline automatically updates Auto Scaling groups to use the new AMI. (9) Within 24 hours, all EC2 instances are running the latest patched AMI. (10) The company maintains a 7-day patch window without manual intervention. EC2 Image Builder automated the patching process, ensuring instances are always up-to-date.

Detailed Example 3: Multi-Account AMI Distribution

A large enterprise wants to distribute approved AMIs to 50 AWS accounts. Here's how they use EC2 Image Builder: (1) They create a centralized "AMI Factory" account where Image Builder pipelines run. (2) They create pipelines for different workload types: web servers, database servers, application servers. (3) They configure distribution settings to share AMIs with all 50 accounts. (4) They enable AMI encryption with a KMS key shared across accounts. (5) Pipelines run weekly, creating new AMIs. (6) Image Builder automatically shares the AMIs with all 50 accounts. (7) Each account receives the AMI and can launch instances immediately. (8) The central team maintains a single source of truth for approved AMIs. (9) Accounts cannot modify the shared AMIs, ensuring consistency. (10) The company achieves centralized AMI management across the organization. EC2 Image Builder enabled scalable, centralized AMI distribution.

Must Know (Critical Facts):

  • EC2 Image Builder is free - you only pay for underlying resources (EC2 instances, storage)
  • Components are reusable scripts that can be shared across pipelines
  • AWS provides pre-built components for common tasks (CIS hardening, software installation)
  • Pipelines can be scheduled or triggered manually
  • Image Builder supports both Linux and Windows AMIs
  • AMIs can be encrypted with KMS keys during creation
  • Distribution can copy AMIs to multiple regions and share with multiple accounts
  • Test components must pass for AMI creation to proceed

When to use (Comprehensive):

  • ✅ Use when: You need to create hardened AMIs with consistent security configurations
  • ✅ Use when: You want to automate AMI patching and updates
  • ✅ Use when: Compliance requires CIS benchmarks or other security standards
  • ✅ Use when: You need to distribute AMIs across multiple regions and accounts
  • ✅ Use when: You want to validate AMIs with automated tests before deployment
  • ✅ Use when: You need to maintain a golden AMI library for your organization
  • ❌ Don't use when: You only need to create AMIs occasionally (manual creation is simpler)
  • ❌ Don't use when: You use containerized workloads exclusively (use ECR image scanning instead)

Amazon Inspector - Continuous Vulnerability Scanning

What it is: Amazon Inspector is an automated vulnerability management service that continuously scans EC2 instances and container images for software vulnerabilities and network exposure. It provides risk scores and remediation guidance.

Why it exists: Manually scanning for vulnerabilities is time-consuming and often missed. New vulnerabilities are discovered daily. Organizations need automated, continuous scanning to identify and remediate vulnerabilities before they're exploited.

Real-world analogy: Amazon Inspector is like a security guard who continuously patrols your building, checking for unlocked doors, broken windows, and security weaknesses. The guard reports issues immediately and provides recommendations for fixes.

How it works (Detailed step-by-step):

  1. Activation: You activate Inspector in your AWS account (no agents required for EC2 scanning).
  2. Discovery: Inspector automatically discovers EC2 instances and ECR container images in your account.
  3. Scanning: Inspector continuously scans for vulnerabilities using the Systems Manager agent (for EC2) or image scanning (for ECR).
  4. Vulnerability Database: Inspector compares installed software against CVE (Common Vulnerabilities and Exposures) databases.
  5. Network Reachability: Inspector analyzes network configurations to identify instances exposed to the internet.
  6. Risk Scoring: Inspector assigns risk scores to findings based on CVSS (Common Vulnerability Scoring System) and network exposure.
  7. Findings: Inspector generates findings for each vulnerability, including severity, affected package, and remediation guidance.
  8. Integration: Findings are sent to Security Hub for centralized management and EventBridge for automated remediation.
  9. Continuous Monitoring: Inspector rescans automatically when new vulnerabilities are published or instances are updated.

📊 Amazon Inspector Scanning Flow Diagram:

graph TB
    subgraph "AWS Account"
        EC2_1[EC2 Instance 1<br/>SSM Agent]
        EC2_2[EC2 Instance 2<br/>SSM Agent]
        ECR[ECR Repository<br/>Container Images]
    end
    
    subgraph "Amazon Inspector"
        Discovery[Auto Discovery<br/>EC2 & ECR]
        Scanner[Vulnerability Scanner<br/>CVE Database]
        Network[Network Reachability<br/>Analyzer]
        Risk[Risk Scoring<br/>CVSS + Exposure]
    end
    
    subgraph "Findings & Actions"
        Findings[Inspector Findings<br/>Severity + Remediation]
        SecurityHub[Security Hub<br/>Centralized View]
        EventBridge[EventBridge<br/>Automated Response]
        Lambda[Lambda Function<br/>Auto-Remediation]
    end
    
    EC2_1 --> Discovery
    EC2_2 --> Discovery
    ECR --> Discovery
    
    Discovery --> Scanner
    Discovery --> Network
    
    Scanner --> Risk
    Network --> Risk
    
    Risk --> Findings
    
    Findings --> SecurityHub
    Findings --> EventBridge
    EventBridge --> Lambda
    
    style Findings fill:#c8e6c9
    style Scanner fill:#e1f5fe
    style Risk fill:#fff3e0

See: diagrams/04_domain3_inspector_scanning_flow.mmd

Diagram Explanation (Detailed):

The diagram shows Amazon Inspector's continuous vulnerability scanning workflow. Inspector automatically discovers EC2 instances (with SSM Agent installed) and ECR container images in the AWS account. For EC2 instances, Inspector uses the Systems Manager agent to inventory installed software packages. For ECR images, Inspector scans image layers during push. The vulnerability scanner compares discovered software against CVE databases to identify known vulnerabilities. Simultaneously, the network reachability analyzer examines security groups, NACLs, and route tables to determine which instances are exposed to the internet. The risk scoring engine combines vulnerability severity (CVSS scores) with network exposure to calculate overall risk scores. High-risk findings (critical vulnerabilities on internet-exposed instances) receive higher priority. Inspector generates findings with detailed information: affected package, CVE ID, severity, remediation guidance, and risk score. Findings are automatically sent to Security Hub for centralized security management across accounts. Findings are also sent to EventBridge, enabling automated remediation workflows. For example, an EventBridge rule can trigger a Lambda function to automatically patch vulnerable instances or isolate them from the network. Inspector continuously rescans as new vulnerabilities are published or instances are updated, ensuring ongoing protection.

Detailed Example 1: Identifying and Remediating Critical Vulnerabilities

A company discovers a critical vulnerability in their EC2 fleet. Here's how Inspector helps: (1) Inspector is activated and continuously scanning all EC2 instances. (2) A new critical CVE is published for the Apache web server. (3) Inspector rescans all instances and identifies 15 instances running the vulnerable Apache version. (4) Inspector generates findings with severity "CRITICAL" and risk score 9.8. (5) Findings are sent to Security Hub and EventBridge. (6) An EventBridge rule triggers a Lambda function for critical findings. (7) The Lambda function creates a Systems Manager maintenance window to patch the affected instances. (8) Systems Manager applies the Apache security update to all 15 instances. (9) Inspector rescans the instances and confirms the vulnerability is remediated. (10) The findings are marked as resolved. Inspector identified the vulnerability within hours of publication and enabled automated remediation.

Detailed Example 2: Preventing Deployment of Vulnerable Container Images

A company wants to prevent vulnerable container images from being deployed. Here's how they use Inspector: (1) They enable Inspector ECR scanning for all repositories. (2) They configure scan-on-push so images are scanned immediately when pushed. (3) A developer pushes a new container image to ECR. (4) Inspector scans the image and finds a high-severity vulnerability in a Python library. (5) Inspector generates a finding and sends it to EventBridge. (6) An EventBridge rule triggers a Lambda function that updates the ECR repository policy to prevent pulling images with high-severity findings. (7) The CI/CD pipeline attempts to deploy the image but fails because the image cannot be pulled. (8) The developer receives a notification with the Inspector finding and remediation guidance. (9) The developer updates the Python library and pushes a new image. (10) Inspector scans the new image, finds no vulnerabilities, and allows deployment. Inspector prevented vulnerable images from reaching production.

Detailed Example 3: Prioritizing Remediation Based on Network Exposure

A security team has limited resources and needs to prioritize vulnerability remediation. Here's how Inspector helps: (1) Inspector scans 500 EC2 instances and finds vulnerabilities in 200 of them. (2) Inspector's network reachability analyzer determines that 50 instances are exposed to the internet. (3) Inspector calculates risk scores combining vulnerability severity and network exposure. (4) Instances with critical vulnerabilities AND internet exposure receive risk scores of 9.0-10.0. (5) Instances with critical vulnerabilities but NO internet exposure receive risk scores of 6.0-7.0. (6) The security team sorts findings by risk score in Security Hub. (7) They prioritize patching the 10 instances with risk scores above 9.0 (critical vulnerabilities + internet exposure). (8) They schedule patching for the remaining instances based on risk scores. (9) Within 24 hours, the highest-risk instances are patched. (10) The team efficiently allocated resources to address the most critical risks first. Inspector's risk scoring enabled data-driven prioritization.

Must Know (Critical Facts):

  • Inspector requires the Systems Manager agent for EC2 scanning (automatically installed on Amazon Linux 2 and newer)
  • Inspector scans ECR images automatically when scan-on-push is enabled
  • Inspector provides network reachability findings showing which instances are exposed to the internet
  • Risk scores combine vulnerability severity (CVSS) with network exposure
  • Inspector integrates with Security Hub for centralized findings management
  • Inspector findings can trigger automated remediation via EventBridge
  • Inspector continuously rescans as new CVEs are published
  • Inspector is priced per instance scanned per month (no upfront costs)

When to use (Comprehensive):

  • ✅ Use when: You need continuous vulnerability scanning for EC2 instances
  • ✅ Use when: You want to scan container images for vulnerabilities before deployment
  • ✅ Use when: You need to identify network exposure and prioritize remediation
  • ✅ Use when: Compliance requires regular vulnerability assessments
  • ✅ Use when: You want to automate vulnerability detection and remediation
  • ✅ Use when: You need risk-based prioritization of vulnerabilities
  • ❌ Don't use when: You only run serverless workloads (Lambda) with no EC2 or containers
  • ❌ Don't use when: You have a third-party vulnerability scanner that meets your needs

Systems Manager Patch Manager - Automated Patching

What it is: AWS Systems Manager Patch Manager automates the process of patching EC2 instances and on-premises servers with security updates and other patches. It provides patch compliance reporting and can patch instances on a schedule.

Why it exists: Manually patching servers is time-consuming, error-prone, and often delayed. Unpatched systems are a major security risk. Organizations need automated patching to ensure systems are up-to-date without manual intervention.

Real-world analogy: Patch Manager is like an automated maintenance crew that visits your building on a schedule, fixes known issues, and reports on the building's condition. You don't need to remember to call them - they show up automatically.

How it works (Detailed step-by-step):

  1. Patch Baseline: You define a patch baseline specifying which patches to install (e.g., all security patches, critical patches only).
  2. Maintenance Window: You create a maintenance window defining when patching should occur (e.g., Sundays 2-4 AM).
  3. Target Selection: You specify which instances to patch using tags, instance IDs, or resource groups.
  4. Patch Scan: Patch Manager scans instances to identify missing patches based on the patch baseline.
  5. Patch Installation: During the maintenance window, Patch Manager installs missing patches on target instances.
  6. Reboot: If required, Patch Manager reboots instances after patching (configurable).
  7. Compliance Reporting: Patch Manager reports patch compliance status for each instance.
  8. Integration: Patch compliance data is sent to Security Hub and can trigger EventBridge rules.

Detailed Example 1: Automated Monthly Patching

A company wants to patch all EC2 instances monthly. Here's how they use Patch Manager: (1) They create a patch baseline that approves all security patches released in the last 7 days. (2) They create a maintenance window scheduled for the first Sunday of each month, 2-4 AM. (3) They register all EC2 instances with the tag "Environment: Production" as targets. (4) On the first Sunday, the maintenance window opens. (5) Patch Manager scans all target instances and identifies missing patches. (6) Patch Manager installs missing patches on all instances. (7) Instances are rebooted if required by the patches. (8) Patch Manager reports compliance status: 95% of instances are now compliant. (9) The 5% non-compliant instances had patching failures (logged for investigation). (10) The company maintains a consistent patching schedule without manual intervention. Patch Manager automated monthly patching across the fleet.

Must Know (Critical Facts):

  • Patch Manager requires the Systems Manager agent on instances
  • Patch baselines define which patches to install (can be customized per OS)
  • Maintenance windows define when patching occurs (can have multiple windows)
  • Patch Manager can patch both EC2 instances and on-premises servers
  • Compliance reporting shows which instances are patched and which are not
  • Patch Manager integrates with Security Hub for centralized compliance visibility
  • Patch Manager can be configured to reboot instances automatically or skip reboots

Chapter Summary

What We Covered

This chapter covered Domain 3: Infrastructure Security (20% of exam), including:

  • Edge Security: WAF, CloudFront, Shield, load balancers, Route 53, DDoS protection
  • Network Security: VPC, security groups, NACLs, Network Firewall, segmentation
  • Compute Security: EC2 patching, AMI hardening, vulnerability scanning, IAM roles
  • Network Connectivity: VPN, Direct Connect, Transit Gateway, VPC endpoints, PrivateLink
  • Troubleshooting: Reachability Analyzer, VPC Flow Logs, Traffic Mirroring

Critical Takeaways

  1. Defense in Depth: Layer multiple security controls (WAF + Shield + security groups + NACLs)
  2. WAF: Protects against OWASP Top 10, SQL injection, XSS, bot attacks
  3. Shield Standard: Free DDoS protection, Shield Advanced for enhanced protection
  4. Security Groups: Stateful, allow rules only, instance-level
  5. NACLs: Stateless, allow and deny rules, subnet-level
  6. Network Firewall: Stateful inspection, IDS/IPS, domain filtering
  7. VPC Endpoints: Keep traffic off public internet, interface and gateway endpoints
  8. Systems Manager: Patch management, Session Manager, secure remote access
  9. Inspector: Vulnerability scanning for EC2 and containers

Self-Assessment Checklist

Test yourself before moving on:

  • I can design a layered edge security architecture
  • I understand the difference between security groups and NACLs
  • I know when to use WAF, Shield, and Network Firewall
  • I can design network segmentation strategies
  • I understand VPC endpoints and PrivateLink
  • I know how to secure EC2 instances (patching, hardening, IAM roles)
  • I can troubleshoot network connectivity issues
  • I understand VPN and Direct Connect security
  • I know how to use Systems Manager for secure remote access
  • I can design a secure compute environment

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-25 (Edge and Network Security)
  • Domain 3 Bundle 2: Questions 26-50 (Compute Security)
  • Network Security Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: WAF rules, Network Firewall, VPC endpoints, Systems Manager
  • Focus on: Service selection, layered defense, troubleshooting

Quick Reference Card

Key Services:

  • WAF: Web application firewall, OWASP Top 10 protection
  • Shield: DDoS protection (Standard free, Advanced paid)
  • Network Firewall: Stateful inspection, IDS/IPS
  • Security Groups: Stateful, instance-level, allow only
  • NACLs: Stateless, subnet-level, allow and deny
  • VPC Endpoints: Private connectivity to AWS services
  • Systems Manager: Patch management, Session Manager
  • Inspector: Vulnerability scanning

Decision Points:

  • Need web application protection? → WAF
  • Need DDoS protection? → Shield (Standard or Advanced)
  • Need network-layer filtering? → Network Firewall or NACLs
  • Need instance-level filtering? → Security Groups
  • Need to keep traffic private? → VPC Endpoints or PrivateLink
  • Need secure remote access? → Session Manager
  • Need vulnerability scanning? → Inspector
  • Need automated patching? → Systems Manager Patch Manager

Security Best Practices:

  1. Implement defense in depth (multiple layers)
  2. Use security groups as primary firewall
  3. Use NACLs for subnet-level protection
  4. Enable VPC Flow Logs for visibility
  5. Use VPC endpoints to keep traffic private
  6. Automate patching with Systems Manager
  7. Scan for vulnerabilities with Inspector
  8. Use Session Manager instead of SSH/RDP
  9. Implement least privilege for IAM roles
  10. Enable Shield Advanced for critical workloads

Chapter 3 Complete

Next Chapter: 05_domain4_iam - Identity and Access Management (16% of exam)


Chapter Summary

What We Covered

This chapter explored Infrastructure Security, the largest domain covering network and compute security:

Edge Security Controls: Designing security for edge services (WAF, CloudFront, Shield, load balancers, Route 53), protecting against OWASP Top 10 and DDoS attacks, implementing layered defense strategies, and applying geographic and rate-based restrictions.

Network Security Controls: Implementing network segmentation with security groups, NACLs, and Network Firewall, designing network controls to permit/prevent traffic, keeping data off the public internet with Transit Gateway and VPC endpoints, monitoring with VPC Flow Logs and Traffic Mirroring, and securing on-premises connectivity with VPN and Direct Connect.

Compute Security Controls: Provisioning and maintaining EC2 instances (patching, AMIs, Image Builder), using IAM instance roles and service roles, scanning for vulnerabilities with Inspector and ECR, implementing host-based security (firewalls, hardening), and passing secrets securely to compute workloads.

Network Troubleshooting: Analyzing reachability with VPC Reachability Analyzer and Inspector, understanding TCP/IP networking concepts, reading log sources (Route 53, WAF, VPC Flow Logs), and capturing traffic samples with Traffic Mirroring.

Critical Takeaways

  1. Defense in Depth: Layer multiple security controls (CloudFront + WAF + Shield + ALB + security groups + NACLs) to create comprehensive protection. Each layer defends against different attack types.

  2. Least Privilege Networking: Use security groups and NACLs to implement least privilege network access. Only allow required ports and protocols. Regularly audit and remove unused rules.

  3. Private by Default: Keep resources in private subnets whenever possible. Use VPC endpoints to access AWS services without traversing the public internet. Use Transit Gateway for inter-VPC communication.

  4. Patch Management is Critical: Unpatched systems are the #1 vulnerability. Use Systems Manager Patch Manager with maintenance windows for automated patching. Use EC2 Image Builder for golden AMIs with security hardening.

  5. IAM Roles, Not Keys: Never use long-term access keys on EC2 instances. Always use IAM instance roles with temporary credentials. Rotate roles regularly and follow least privilege.

  6. Vulnerability Scanning: Enable Inspector for continuous vulnerability scanning of EC2 instances and ECR for container image scanning. Remediate critical and high-severity findings immediately.

  7. Secrets Management: Never hardcode secrets in code or AMIs. Use Secrets Manager or Parameter Store (SecureString) to store secrets. Inject secrets at runtime using IAM roles.

  8. Network Visibility: Enable VPC Flow Logs for all VPCs to monitor network traffic. Use Traffic Mirroring for deep packet inspection when investigating security incidents.

Self-Assessment Checklist

Test yourself before moving on:

  • I can design edge security architectures with WAF, CloudFront, Shield, and load balancers
  • I understand how to protect against OWASP Top 10 attacks using WAF rules
  • I know how to implement DDoS protection with Shield Standard and Shield Advanced
  • I can design layered defense strategies combining multiple security services
  • I understand how to apply geographic restrictions and rate limiting
  • I can implement network segmentation using security groups, NACLs, and Network Firewall
  • I know the differences between security groups (stateful) and NACLs (stateless)
  • I can design network architectures that keep data off the public internet
  • I understand how to use VPC endpoints (interface and gateway endpoints)
  • I can configure Transit Gateway for secure inter-VPC communication
  • I know how to enable and analyze VPC Flow Logs
  • I understand when to use Traffic Mirroring for deep packet inspection
  • I can secure on-premises connectivity with Site-to-Site VPN and Direct Connect
  • I understand MACsec encryption for Direct Connect
  • I can design automated patching strategies with Systems Manager
  • I know how to create golden AMIs with EC2 Image Builder
  • I understand how to use IAM instance roles and service roles
  • I can configure Inspector for vulnerability scanning
  • I know how to enable ECR image scanning
  • I can implement host-based security (firewalls, hardening)
  • I understand how to pass secrets securely using Secrets Manager and Parameter Store
  • I can troubleshoot network connectivity issues using VPC Reachability Analyzer
  • I know how to read and analyze VPC Flow Logs, WAF logs, and Route 53 query logs

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-25 (Edge and Network Security)
  • Domain 3 Bundle 2: Questions 26-50 (Compute Security and Troubleshooting)
  • Network Security Bundle: All 50 questions (Network-specific scenarios)
  • Edge & Compute Security Bundle: All 50 questions (Edge and compute scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review WAF rule types and managed rule groups
  • Practice designing network segmentation strategies
  • Study the differences between security groups and NACLs
  • Focus on VPC endpoint types and use cases
  • Review Systems Manager patching and EC2 Image Builder pipelines

Quick Reference Card

Edge Security Services:

  • WAF: Web application firewall (OWASP Top 10, custom rules, rate limiting)
  • Shield Standard: Free DDoS protection (Layer 3/4)
  • Shield Advanced: Enhanced DDoS protection with DRT support ($3,000/month)
  • CloudFront: CDN with edge security features (geo-blocking, signed URLs, OAI)
  • Route 53: DNS with health checks and failover

Network Security Services:

  • Security Groups: Stateful firewall at instance level (allow rules only)
  • NACLs: Stateless firewall at subnet level (allow and deny rules)
  • Network Firewall: Managed firewall with Suricata rules (stateful and stateless)
  • VPC Endpoints: Private connectivity to AWS services (interface and gateway)
  • Transit Gateway: Hub-and-spoke network architecture for VPC connectivity
  • VPC Flow Logs: Network traffic logging (accepted/rejected connections)
  • Traffic Mirroring: Deep packet inspection for security analysis

Compute Security Services:

  • Systems Manager: Patch management, session management, automation
  • EC2 Image Builder: Automated AMI creation with security hardening
  • Inspector: Vulnerability scanning for EC2 and containers
  • ECR: Container registry with image scanning
  • Secrets Manager: Secrets storage with automatic rotation
  • Parameter Store: Configuration and secrets storage (SecureString with KMS)

Key Concepts:

  • Stateful vs Stateless: Security groups track connections (stateful), NACLs don't (stateless)
  • Defense in Depth: Multiple layers of security controls
  • Least Privilege: Only allow required network access
  • Golden AMI: Pre-hardened AMI with security configurations
  • Instance Role: IAM role attached to EC2 instance for temporary credentials

Decision Points:

  • Web application protection → WAF + CloudFront + ALB
  • DDoS protection → Shield Standard (free) or Shield Advanced (enhanced)
  • Network segmentation → Security groups (instance-level) + NACLs (subnet-level) + Network Firewall (VPC-level)
  • Private AWS service access → VPC endpoints (interface or gateway)
  • Inter-VPC communication → Transit Gateway (hub-and-spoke) or VPC peering (point-to-point)
  • Vulnerability scanning → Inspector (EC2) or ECR (containers)
  • Secrets management → Secrets Manager (with rotation) or Parameter Store (simple secrets)
  • Network troubleshooting → VPC Reachability Analyzer (connectivity) or Traffic Mirroring (deep inspection)

Exam Tips:

  • Know the difference between Shield Standard (free, automatic) and Shield Advanced (paid, DRT support)
  • Understand WAF rule types: rate-based, IP set, geo-match, string match, SQL injection, XSS
  • Remember that security groups are stateful (return traffic automatically allowed) and NACLs are stateless (must explicitly allow return traffic)
  • VPC endpoints keep traffic private (no internet gateway needed)
  • Inspector scans for vulnerabilities and network reachability issues
  • Always use IAM instance roles, never hardcode access keys
  • Systems Manager Session Manager replaces SSH/RDP (no bastion hosts needed)


Chapter Summary

What We Covered

This chapter explored AWS infrastructure security across four critical areas:

Edge Security Controls

  • Edge security strategies using WAF, CloudFront, Shield, load balancers, and Route 53
  • Selecting edge services based on threats (OWASP Top 10, DDoS attacks)
  • Implementing protections for vulnerable software and applications
  • Designing layered defense strategies combining multiple edge services
  • Applying geographic restrictions and rate limiting

Network Security Controls

  • Network segmentation using security groups, NACLs, and Network Firewall
  • Designing network controls to permit or prevent traffic
  • Keeping data off the public internet with Transit Gateway, VPC endpoints, and PrivateLink
  • Network telemetry using VPC Flow Logs and Traffic Mirroring
  • Secure on-premises connectivity with VPN, Direct Connect, and MACsec
  • Removing unnecessary network access

Compute Workload Security

  • EC2 provisioning and maintenance (patching, snapshots, AMIs, Image Builder)
  • IAM instance roles and service roles for compute workloads
  • Vulnerability scanning with Inspector and ECR image scanning
  • Host-based security (firewalls, OS hardening, CIS benchmarks)
  • Passing secrets securely to compute workloads

Network Security Troubleshooting

  • Analyzing reachability with VPC Reachability Analyzer and Inspector
  • Understanding TCP/IP networking concepts for troubleshooting
  • Reading log sources (Route 53 logs, WAF logs, VPC Flow Logs)
  • Capturing traffic samples with Traffic Mirroring for analysis

Critical Takeaways

  1. WAF protects web applications: Deploy AWS WAF on CloudFront, ALB, or API Gateway to protect against OWASP Top 10 attacks
  2. Shield protects against DDoS: Use Shield Standard (free) for basic protection, Shield Advanced for enhanced DDoS protection and cost protection
  3. Layered defense is essential: Combine CloudFront + WAF + ALB + security groups for defense in depth
  4. Security groups are stateful: Return traffic is automatically allowed; use for instance-level security
  5. NACLs are stateless: Must explicitly allow both inbound and outbound traffic; use for subnet-level security
  6. Network Firewall for advanced filtering: Use AWS Network Firewall for stateful inspection, intrusion prevention, and domain filtering
  7. VPC endpoints keep traffic private: Use interface endpoints (PrivateLink) and gateway endpoints to access AWS services without internet
  8. Transit Gateway centralizes connectivity: Use Transit Gateway to connect multiple VPCs and on-premises networks securely
  9. Inspector scans continuously: Enable Inspector for continuous vulnerability scanning of EC2 instances and container images
  10. Systems Manager for patching: Use Systems Manager Patch Manager for automated patching across EC2 fleets
  11. Instance roles over access keys: Always use IAM instance roles instead of embedding access keys in EC2 instances
  12. Secrets Manager for secrets: Use Secrets Manager or Parameter Store (SecureString) to pass secrets to compute workloads

Self-Assessment Checklist

Test yourself before moving on:

Edge Security:

  • I can design edge security strategies for different application types (public website, API, mobile backend)
  • I understand how to configure AWS WAF rules to protect against OWASP Top 10 attacks
  • I know when to use Shield Standard vs Shield Advanced
  • I can design layered defense architectures combining multiple edge services
  • I understand how to implement geographic restrictions and rate limiting

Network Security:

  • I can design network segmentation strategies using security groups and NACLs
  • I understand the differences between security groups, NACLs, and Network Firewall
  • I know how to use VPC endpoints to keep traffic off the public internet
  • I can design Transit Gateway architectures for multi-VPC connectivity
  • I understand how to configure VPC Flow Logs and Traffic Mirroring
  • I can design secure on-premises connectivity using VPN and Direct Connect

Compute Security:

  • I can design automated patching strategies using Systems Manager
  • I understand how to create hardened AMIs using EC2 Image Builder
  • I know how to configure IAM instance roles and service roles properly
  • I can enable and interpret Inspector vulnerability findings
  • I understand how to implement host-based security (firewalls, hardening)
  • I can pass secrets securely to EC2 instances and containers

Troubleshooting:

  • I can use VPC Reachability Analyzer to diagnose connectivity issues
  • I understand TCP/IP networking concepts (ports, protocols, OSI model)
  • I can read and interpret VPC Flow Logs to identify network issues
  • I know how to use Traffic Mirroring to capture and analyze network traffic
  • I can troubleshoot security group and NACL rule issues

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-25 (Edge and Network Security)
  • Domain 3 Bundle 2: Questions 26-50 (Compute Security and Troubleshooting)
  • Network Security Bundle: Questions 1-50 (Network-specific scenarios)
  • Edge & Compute Security Bundle: Questions 1-50 (Edge and compute scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review WAF rule types and when to use managed rule groups vs custom rules
  • Practice designing network segmentation with security groups and NACLs
  • Focus on understanding VPC endpoints and PrivateLink architectures
  • Review Systems Manager capabilities for patching and configuration management

Quick Reference Card

Key Services:

  • AWS WAF: Web application firewall protecting against OWASP Top 10
  • Shield: DDoS protection (Standard free, Advanced paid with enhanced features)
  • CloudFront: CDN with integrated security features (WAF, Shield, geo-blocking)
  • Security Groups: Stateful firewall at instance level
  • NACLs: Stateless firewall at subnet level
  • Network Firewall: Advanced stateful firewall with IPS/IDS capabilities
  • VPC Endpoints: Private connectivity to AWS services (interface and gateway)
  • Transit Gateway: Hub for connecting multiple VPCs and on-premises networks
  • Systems Manager: Patch management, configuration management, session management
  • Inspector: Continuous vulnerability scanning for EC2 and containers
  • EC2 Image Builder: Automated AMI creation with security hardening

Key Concepts:

  • Defense in Depth: Multiple layers of security controls (edge, network, host)
  • Stateful vs Stateless: Security groups (stateful) vs NACLs (stateless)
  • PrivateLink: Private connectivity to AWS services and third-party services
  • Least Privilege: Minimal permissions for instance roles and security group rules
  • Immutable Infrastructure: Replace instances instead of patching in place
  • Golden AMI: Pre-hardened AMI used as base for all instances

Decision Points:

  • Web application protection → AWS WAF on CloudFront/ALB/API Gateway
  • DDoS protection → Shield Standard (basic) or Shield Advanced (enhanced)
  • Instance-level firewall → Security groups (stateful, allow rules only)
  • Subnet-level firewall → NACLs (stateless, allow and deny rules)
  • Advanced network filtering → Network Firewall (IPS/IDS, domain filtering)
  • Private AWS service access → VPC endpoints (interface or gateway)
  • Multi-VPC connectivity → Transit Gateway (hub-and-spoke)
  • Automated patching → Systems Manager Patch Manager
  • Vulnerability scanning → Inspector (continuous) or ECR scanning (on push)
  • Secure remote access → Systems Manager Session Manager (no bastion needed)
  • Pass secrets to instances → Secrets Manager or Parameter Store (SecureString)

  • Subnet-level firewall → NACLs (stateless, allow and deny rules)
  • Advanced filtering → Network Firewall (stateful, IPS/IDS, domain filtering)
  • Private AWS service access → VPC endpoints (interface or gateway)
  • Multi-VPC connectivity → Transit Gateway (hub-and-spoke)
  • Patch management → Systems Manager Patch Manager (automated)
  • Vulnerability scanning → Inspector (continuous, agent-based or agentless)
  • Secure remote access → Session Manager (no SSH/RDP, no bastion, fully audited)

Chapter Summary

What We Covered

This chapter covered Infrastructure Security, the largest domain at 20% of the SCS-C02 exam. We explored four major task areas:

Task 3.1: Edge Security Controls

  • Designing edge security strategies using AWS WAF, CloudFront, Shield, load balancers, and Route 53
  • Selecting edge services based on anticipated threats (OWASP Top 10, DDoS attacks)
  • Choosing protections based on vulnerabilities (vulnerable software, applications, libraries)
  • Implementing layered defense strategies combining multiple edge services
  • Applying restrictions based on geography, geolocation, and rate limiting

Task 3.2: Network Security Controls

  • Implementing network segmentation using security groups, NACLs, and Network Firewall
  • Designing network controls to permit or prevent traffic (stateful vs. stateless filtering)
  • Keeping data off the public internet using Transit Gateway, VPC endpoints, and Lambda in VPCs
  • Determining network telemetry sources (VPC Flow Logs, Traffic Mirroring)
  • Securing on-premises connectivity using VPN, Direct Connect, and MACsec
  • Identifying and removing unnecessary network access

Task 3.3: Compute Workload Security

  • Provisioning and maintaining EC2 instances (patching, snapshots, AMIs, EC2 Image Builder)
  • Using IAM instance roles and service roles to authorize compute workloads
  • Scanning for vulnerabilities using Inspector and ECR image scanning
  • Implementing host-based security (firewalls, hardening, CIS benchmarks)
  • Passing secrets and credentials securely to compute workloads

Task 3.4: Network Security Troubleshooting

  • Analyzing reachability using VPC Reachability Analyzer and Inspector Network Reachability
  • Understanding TCP/IP networking concepts (TCP vs. UDP, ports, OSI model)
  • Reading log sources (Route 53 query logs, WAF logs, VPC Flow Logs)
  • Capturing traffic samples using Traffic Mirroring for deep packet inspection

Critical Takeaways

  1. Defense in Depth is Essential: Never rely on a single security control. Layer edge security (WAF, Shield), network security (security groups, NACLs, Network Firewall), and host security (OS hardening, Inspector).

  2. Security Groups are Stateful, NACLs are Stateless: Security groups automatically allow return traffic. NACLs require explicit rules for both inbound and outbound traffic.

  3. PrivateLink Keeps Data Private: Use VPC endpoints (interface endpoints) to access AWS services without traversing the public internet. This reduces exposure and improves security.

  4. Patch Management is Continuous: Use Systems Manager Patch Manager with maintenance windows for automated patching. Consider immutable infrastructure (replace instances instead of patching).

  5. Inspector Provides Continuous Scanning: Inspector continuously scans EC2 instances and container images for vulnerabilities and network exposure. Remediate critical findings immediately.

  6. Session Manager Replaces Bastions: Never use SSH/RDP with bastion hosts. Use Session Manager for secure, audited remote access without opening ports or managing keys.

  7. WAF Protects Web Applications: AWS WAF protects against OWASP Top 10 threats (SQL injection, XSS, etc.). Use managed rule groups for common threats and custom rules for application-specific protection.

  8. Shield Advanced for DDoS: Shield Standard is free and provides basic DDoS protection. Shield Advanced adds DDoS Response Team (DRT) support, cost protection, and advanced detection.

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Edge Security:

  • Design a layered edge security architecture using CloudFront, WAF, and Shield
  • Configure AWS WAF rules to protect against SQL injection and XSS attacks
  • Explain the difference between Shield Standard and Shield Advanced
  • Implement rate limiting and geo-blocking using WAF
  • Choose between ALB and CloudFront for different application architectures

Network Security:

  • Design network segmentation using public and private subnets
  • Configure security groups and NACLs with appropriate rules
  • Explain the difference between stateful and stateless filtering
  • Implement VPC endpoints for private access to S3 and other AWS services
  • Design a Transit Gateway architecture for multi-VPC connectivity
  • Configure Network Firewall for advanced threat protection

Compute Security:

  • Create a golden AMI using EC2 Image Builder with security hardening
  • Configure Systems Manager Patch Manager for automated patching
  • Assign IAM instance roles to EC2 instances for least privilege access
  • Enable Inspector for continuous vulnerability scanning
  • Implement ECR image scanning for container security
  • Pass secrets to EC2 instances using Secrets Manager or Parameter Store

Troubleshooting:

  • Use VPC Reachability Analyzer to diagnose connectivity issues
  • Interpret VPC Flow Logs to identify rejected traffic
  • Analyze WAF logs to understand blocked requests
  • Configure Traffic Mirroring for deep packet inspection

Decision-Making:

  • Choose between security groups and NACLs for different scenarios
  • Determine when to use Network Firewall vs. security groups
  • Select between VPN and Direct Connect for on-premises connectivity
  • Decide when to use Session Manager vs. EC2 Instance Connect

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-50 (focus on edge and network security)
  • Domain 3 Bundle 2: Questions 51-100 (focus on compute security and troubleshooting)
  • Network Security Bundle: Questions covering VPC, security groups, NACLs, Network Firewall, WAF, Shield
  • Edge & Compute Security Bundle: Questions covering CloudFront, WAF, Shield, ALB, Lambda, EC2
  • Full Practice Test 1: Domain 3 questions (10 questions, 20% of exam)

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • Security Groups vs. NACLs (if you struggled with stateful vs. stateless questions)
    • VPC Endpoints and PrivateLink (if you struggled with private connectivity questions)
    • AWS WAF Configuration (if you struggled with web application protection questions)
    • Systems Manager Patch Manager (if you struggled with patch management questions)
  • Focus on:
    • Understanding the differences between security groups, NACLs, and Network Firewall
    • Memorizing common WAF rule patterns for OWASP Top 10
    • Practicing VPC Reachability Analyzer for troubleshooting
    • Understanding when to use Session Manager vs. bastion hosts

Quick Reference Card

Key Services:

  • AWS WAF: Web application firewall protecting against OWASP Top 10 (SQL injection, XSS, etc.)
  • Shield: DDoS protection (Standard is free, Advanced adds DRT support)
  • CloudFront: CDN with edge security features (geo-blocking, signed URLs, OAI)
  • Security Groups: Stateful firewall at instance/ENI level (allow rules only)
  • NACLs: Stateless firewall at subnet level (allow and deny rules)
  • Network Firewall: Advanced stateful firewall with IPS/IDS capabilities
  • VPC Endpoints: Private connectivity to AWS services (interface and gateway)
  • Transit Gateway: Hub for connecting multiple VPCs and on-premises networks
  • Systems Manager: Patch management, configuration management, session management
  • Inspector: Continuous vulnerability scanning for EC2 and containers
  • EC2 Image Builder: Automated AMI creation with security hardening

Key Concepts:

  • Defense in Depth: Multiple layers of security controls (edge, network, host)
  • Stateful vs. Stateless: Security groups (stateful) automatically allow return traffic; NACLs (stateless) require explicit rules
  • PrivateLink: Private connectivity to AWS services without traversing the public internet
  • Least Privilege: Minimal permissions for instance roles and security group rules
  • Immutable Infrastructure: Replace instances instead of patching in place
  • Golden AMI: Pre-hardened AMI used as base for all instances

Decision Points:

  • Web application protection → AWS WAF on CloudFront/ALB/API Gateway
  • DDoS protection → Shield Standard (basic) or Shield Advanced (enhanced + DRT)
  • Instance-level firewall → Security groups (stateful, allow rules only)
  • Subnet-level firewall → NACLs (stateless, allow and deny rules)
  • Advanced filtering → Network Firewall (stateful, IPS/IDS, domain filtering)
  • Private AWS service access → VPC endpoints (interface or gateway)
  • Multi-VPC connectivity → Transit Gateway (hub-and-spoke)
  • Patch management → Systems Manager Patch Manager (automated)
  • Vulnerability scanning → Inspector (continuous, agent-based or agentless)
  • Secure remote access → Session Manager (no SSH/RDP, no bastion, fully audited)

Next Steps

Before moving to Domain 4:

  1. Review the Quick Reference Card and ensure you can recall all key services and concepts
  2. Practice designing VPC architectures with proper segmentation
  3. Experiment with AWS WAF rules and test against common attacks
  4. Set up Session Manager and practice remote access without SSH

Moving Forward:

  • Domain 4 (Identity and Access Management) will cover how to control access to the infrastructure you learned about in this domain
  • Understanding IAM instance roles is essential for securing compute workloads
  • Network security concepts (security groups, NACLs) will be combined with IAM policies for comprehensive access control

Chapter Summary

What We Covered

This chapter covered Domain 3: Infrastructure Security (20% of the exam), focusing on four critical task areas:

Task 3.1: Design and implement security controls for edge services

  • Edge security strategies using AWS WAF, load balancers, Route 53, CloudFront, and Shield
  • Selecting appropriate edge services based on anticipated threats (OWASP Top 10, DDoS)
  • Selecting protections based on anticipated vulnerabilities and risks
  • Defining layers of defense by combining edge security services
  • Applying restrictions based on geography, geolocation, and rate limiting

Task 3.2: Design and implement network security controls

  • Network segmentation using security groups, NACLs, and Network Firewall
  • Designing network controls to permit or prevent network traffic
  • Keeping data off the public internet using Transit Gateway, VPC endpoints, and Lambda in VPCs
  • Determining which telemetry sources to monitor (VPC Flow Logs, Traffic Mirroring)
  • Designing redundancy and security for on-premises connectivity (VPN, Direct Connect, MACsec)

Task 3.3: Design and implement security controls for compute workloads

  • EC2 provisioning and maintenance (patching, snapshots, AMIs, Image Builder)
  • IAM instance roles and service roles for compute workloads
  • Vulnerability scanning using Inspector and ECR image scanning
  • Host-based security (firewalls, hardening)
  • Passing secrets and credentials securely to compute workloads

Task 3.4: Troubleshoot network security

  • Analyzing reachability using VPC Reachability Analyzer and Inspector
  • Understanding TCP/IP networking concepts (TCP vs. UDP, ports, OSI model)
  • Reading log sources (Route 53 logs, WAF logs, VPC Flow Logs)
  • Capturing traffic samples using Traffic Mirroring

Critical Takeaways

  1. AWS WAF protects web applications: Deploy on CloudFront, ALB, or API Gateway. Use managed rule groups for OWASP Top 10 protection.

  2. Shield Standard is automatic: All AWS customers get basic DDoS protection. Shield Advanced adds enhanced protection and DDoS Response Team (DRT) support.

  3. Security groups are stateful: Return traffic is automatically allowed. Use for instance-level firewalls.

  4. NACLs are stateless: Must explicitly allow both inbound and outbound traffic. Use for subnet-level firewalls.

  5. Network Firewall for advanced filtering: Use for stateful inspection, intrusion prevention (IPS/IDS), and domain filtering.

  6. VPC endpoints keep traffic private: Use interface endpoints for most services, gateway endpoints for S3 and DynamoDB.

  7. Transit Gateway for multi-VPC connectivity: Hub-and-spoke architecture for connecting multiple VPCs and on-premises networks.

  8. Session Manager replaces bastion hosts: No SSH/RDP, no public IPs, fully audited remote access.

  9. Systems Manager Patch Manager automates patching: Use maintenance windows and patch baselines for automated patching.

  10. Inspector scans for vulnerabilities: Enable continuous scanning for EC2 instances and container images.

Self-Assessment Checklist

Test yourself before moving to Domain 4. You should be able to:

Edge Security:

  • Design a layered defense strategy using CloudFront, WAF, and Shield
  • Select appropriate WAF rules for OWASP Top 10 protection
  • Explain when to use Shield Standard vs. Shield Advanced
  • Configure rate-based rules in AWS WAF
  • Implement geo-blocking using CloudFront
  • Explain how AWS WAF integrates with CloudFront, ALB, and API Gateway

Network Security:

  • Design VPC segmentation with public, private, and isolated subnets
  • Explain the difference between security groups and NACLs
  • Design security group rules following least privilege
  • Configure Network Firewall for stateful inspection
  • Explain when to use VPC endpoints vs. NAT Gateway
  • Design a Transit Gateway architecture for multi-VPC connectivity
  • Configure VPC Flow Logs for network monitoring
  • Explain when to use Traffic Mirroring

Compute Security:

  • Design an automated patching strategy using Systems Manager
  • Create hardened AMIs using EC2 Image Builder
  • Configure IAM instance roles for EC2 instances
  • Enable Inspector for continuous vulnerability scanning
  • Configure ECR image scanning on push
  • Explain how to pass secrets to EC2 instances using Secrets Manager
  • Design an immutable infrastructure deployment strategy

Network Troubleshooting:

  • Use VPC Reachability Analyzer to troubleshoot connectivity issues
  • Interpret VPC Flow Logs to identify rejected traffic
  • Analyze WAF logs to identify blocked requests
  • Explain the difference between TCP and UDP
  • Troubleshoot security group and NACL misconfigurations
  • Use Traffic Mirroring to capture packets for analysis

Practice Questions

Recommended Practice Test Bundles:

  • Domain 3 Bundle 1: Questions 161-210 (covers all Task 3.1, 3.2, 3.3, 3.4 topics)
  • Domain 3 Bundle 2: Questions 211-260 (additional practice on weak areas)
  • Network Security Bundle: Questions covering VPC, Security Groups, NACLs, Network Firewall, WAF, Shield
  • Edge & Compute Security Bundle: Questions covering CloudFront, WAF, Shield, ALB, Lambda, EC2

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • Security Groups vs. NACLs (if you struggled with network filtering questions)
    • VPC Endpoints and PrivateLink (if you struggled with private connectivity questions)
    • AWS WAF Rule Configuration (if you struggled with web application protection questions)
    • Systems Manager Patch Manager (if you struggled with patching questions)
  • Focus on:
    • Understanding the difference between stateful (security groups) and stateless (NACLs) firewalls
    • Memorizing when to use interface endpoints vs. gateway endpoints
    • Practicing VPC Flow Logs analysis
    • Understanding the order of WAF rule evaluation

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • AWS WAF: Web application firewall (protects against OWASP Top 10)
  • Shield: DDoS protection (Standard = automatic, Advanced = enhanced + DRT)
  • CloudFront: CDN with edge security features
  • Security Groups: Stateful instance-level firewall (allow rules only)
  • NACLs: Stateless subnet-level firewall (allow and deny rules)
  • Network Firewall: Advanced stateful firewall with IPS/IDS
  • VPC Endpoints: Private connectivity to AWS services
  • Transit Gateway: Hub-and-spoke multi-VPC connectivity
  • Session Manager: Secure remote access without SSH/RDP
  • Systems Manager Patch Manager: Automated patching
  • Inspector: Continuous vulnerability scanning

Key Concepts:

  • Stateful: Return traffic automatically allowed (security groups)
  • Stateless: Must explicitly allow both directions (NACLs)
  • Defense in Depth: Multiple layers of security controls
  • Least Privilege: Minimum necessary permissions
  • Immutable Infrastructure: Replace instances instead of patching in place
  • Golden AMI: Pre-hardened AMI used as base for all instances

Decision Points:

  • Web application protection → AWS WAF on CloudFront/ALB/API Gateway
  • DDoS protection → Shield Standard (basic) or Shield Advanced (enhanced + DRT)
  • Instance-level firewall → Security groups (stateful, allow rules only)
  • Subnet-level firewall → NACLs (stateless, allow and deny rules)
  • Advanced filtering → Network Firewall (stateful, IPS/IDS, domain filtering)
  • Private AWS service access → VPC endpoints (interface or gateway)
  • Multi-VPC connectivity → Transit Gateway (hub-and-spoke)
  • Patch management → Systems Manager Patch Manager (automated)
  • Vulnerability scanning → Inspector (continuous, agent-based or agentless)
  • Secure remote access → Session Manager (no SSH/RDP, no bastion, fully audited)

Common Patterns:

  • CloudFront + WAF + Shield → Layered edge protection
  • Security Groups + NACLs + Network Firewall → Defense in depth
  • VPC Endpoints + Transit Gateway → Private connectivity
  • Session Manager + IAM → Secure remote access
  • Systems Manager + Inspector → Automated patching and scanning

Chapter Summary

What We Covered

This chapter covered Domain 3: Infrastructure Security (20% of the exam), focusing on four critical task areas:

Task 3.1: Design and implement security controls for edge services

  • Edge security strategies using WAF, load balancers, Route 53, CloudFront, and Shield
  • Selecting edge services based on threats (OWASP Top 10, DDoS attacks)
  • Selecting protections based on vulnerabilities (vulnerable software, applications, libraries)
  • Layered defense strategies combining multiple edge services
  • Applying restrictions based on geography, geolocation, and rate limiting

Task 3.2: Design and implement network security controls

  • Network segmentation using security groups, NACLs, and Network Firewall
  • Designing network controls to permit or prevent traffic
  • Keeping data off the public internet using Transit Gateway, VPC endpoints, and Lambda in VPCs
  • Network telemetry using VPC Flow Logs and Traffic Mirroring
  • On-premises connectivity using VPN, Direct Connect, and MACsec
  • Identifying and removing unnecessary network access

Task 3.3: Design and implement security controls for compute workloads

  • EC2 provisioning and maintenance (patching, snapshots, AMIs, Image Builder)
  • IAM instance roles and service roles for compute workloads
  • Vulnerability scanning using Inspector and ECR image scanning
  • Host-based security (firewalls, hardening, CIS benchmarks)
  • Passing secrets securely to compute workloads using Secrets Manager and Parameter Store

Task 3.4: Troubleshoot network security

  • Analyzing reachability using VPC Reachability Analyzer and Inspector
  • TCP/IP networking concepts (UDP vs TCP, ports, OSI model)
  • Reading log sources (Route 53 logs, WAF logs, VPC Flow Logs)
  • Capturing traffic samples using Traffic Mirroring for analysis

Critical Takeaways

  1. WAF protects against OWASP Top 10: Use managed rule groups for common attacks (SQL injection, XSS, bot traffic). Custom rules for application-specific threats.

  2. Shield Standard is free, Shield Advanced costs money: Shield Standard protects against common DDoS attacks. Shield Advanced adds DDoS Response Team, cost protection, and advanced detection.

  3. CloudFront is a CDN with security features: Use it with WAF for edge protection, geo-blocking, signed URLs/cookies, and origin access identity (OAI) for S3.

  4. Security groups are stateful, NACLs are stateless: Security groups automatically allow return traffic. NACLs require explicit rules for both directions.

  5. Network Firewall provides advanced filtering: Use Suricata rules for deep packet inspection, intrusion prevention, and domain filtering.

  6. VPC endpoints keep traffic private: Interface endpoints (PrivateLink) and gateway endpoints (S3, DynamoDB) prevent traffic from traversing the internet.

  7. Transit Gateway centralizes connectivity: Connect multiple VPCs and on-premises networks through a single hub. Use route tables for segmentation.

  8. Systems Manager Session Manager replaces bastion hosts: Provides secure shell access without SSH keys, public IPs, or bastion hosts. All sessions logged to CloudWatch.

  9. EC2 Image Builder automates AMI creation: Build hardened, patched AMIs on a schedule. Automatically test and distribute to multiple regions.

  10. Inspector scans for vulnerabilities: Continuously scans EC2 instances and container images for software vulnerabilities and network exposure.

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Edge Security:

  • Design a WAF rule to block SQL injection attacks
  • Explain the difference between Shield Standard and Shield Advanced
  • Configure CloudFront with WAF and origin access identity (OAI)
  • Implement geo-blocking to restrict access by country
  • Create a rate-based WAF rule to prevent DDoS attacks

Network Security:

  • Design a VPC with public and private subnets using security groups and NACLs
  • Explain the difference between stateful (security groups) and stateless (NACLs) filtering
  • Configure Network Firewall with Suricata rules for intrusion prevention
  • Design a Transit Gateway architecture for multi-VPC connectivity
  • Implement VPC endpoints to keep S3 traffic private

Compute Security:

  • Create an EC2 Image Builder pipeline for automated AMI creation
  • Configure Systems Manager Patch Manager for automated patching
  • Assign an IAM instance role to an EC2 instance for S3 access
  • Enable Inspector vulnerability scanning for EC2 instances
  • Harden an EC2 instance using CIS benchmarks

Network Troubleshooting:

  • Use VPC Reachability Analyzer to diagnose connectivity issues
  • Read VPC Flow Logs to identify rejected traffic
  • Analyze WAF logs to identify blocked requests
  • Configure Traffic Mirroring to capture packets for analysis
  • Troubleshoot security group and NACL rule conflicts

Practice Questions

Try these from your practice test bundles:

  • Domain 3 Bundle 1: Questions 1-25 (focus on edge and network security)
  • Domain 3 Bundle 2: Questions 26-50 (focus on compute security and troubleshooting)
  • Network Security Bundle: Questions covering VPC, security groups, NACLs, Network Firewall, WAF, Shield
  • Edge Compute Security Bundle: Questions covering CloudFront, WAF, Shield, ALB/NLB, Lambda, EC2
  • Full Practice Test 1: Domain 3 questions (10 questions, 20% of exam)

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review the differences between security groups and NACLs
  • Practice designing VPC architectures with proper segmentation
  • Focus on understanding WAF rule types and managed rule groups
  • Revisit the Systems Manager Session Manager and EC2 Image Builder workflows

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • WAF: Web application firewall for OWASP Top 10 protection
  • Shield: DDoS protection (Standard free, Advanced paid)
  • CloudFront: CDN with edge security features
  • Security Groups: Stateful firewall at instance level
  • NACLs: Stateless firewall at subnet level
  • Network Firewall: Advanced filtering with Suricata rules
  • Transit Gateway: Hub for multi-VPC and on-premises connectivity
  • VPC Endpoints: Private connectivity to AWS services
  • Systems Manager: Patch management, Session Manager, automation
  • Inspector: Vulnerability scanning for EC2 and containers
  • EC2 Image Builder: Automated AMI creation and hardening

Key Concepts:

  • OWASP Top 10: Common web application vulnerabilities (SQL injection, XSS, etc.)
  • DDoS: Distributed Denial of Service attacks (volumetric, protocol, application layer)
  • Stateful vs Stateless: Security groups automatically allow return traffic, NACLs don't
  • Defense in Depth: Multiple layers of security (WAF + Shield + security groups + NACLs)
  • PrivateLink: Private connectivity to AWS services without internet gateway
  • Bastion Host Alternative: Systems Manager Session Manager for secure shell access
  • Golden AMI: Hardened, patched AMI used as a template for all instances
  • CIS Benchmarks: Industry-standard security configuration guidelines

Decision Points:

  • Need web application protection → WAF with managed rule groups
  • Need DDoS protection → Shield Standard (free) or Shield Advanced (paid with DRT)
  • Need edge caching and security → CloudFront with WAF and OAI
  • Need instance-level firewall → Security groups (stateful)
  • Need subnet-level firewall → NACLs (stateless)
  • Need advanced filtering → Network Firewall with Suricata rules
  • Need multi-VPC connectivity → Transit Gateway with route tables
  • Need private AWS service access → VPC endpoints (interface or gateway)
  • Need secure shell access → Systems Manager Session Manager (no SSH keys)
  • Need vulnerability scanning → Inspector for EC2 and ECR
  • Need automated patching → Systems Manager Patch Manager
  • Need hardened AMIs → EC2 Image Builder with CIS benchmarks

Common Troubleshooting:

  • Can't connect to EC2 → Check security group inbound rules, NACL rules, route tables
  • VPC endpoint not working → Check endpoint policy, security group, route tables
  • WAF blocking legitimate traffic → Review WAF logs, adjust rule priorities, use count mode
  • Inspector not scanning → Check IAM permissions, SSM agent installed, network connectivity
  • Session Manager not connecting → Check IAM permissions, SSM agent, VPC endpoints

You're now ready for Chapter 4: Identity and Access Management!

The next chapter will teach you how to control access to the infrastructure you just learned about.


Chapter 4: Identity and Access Management (16% of exam)

Chapter Overview

What you'll learn:

  • Authentication mechanisms and identity federation
  • Authorization with IAM policies and permissions
  • Multi-factor authentication (MFA) and credential management
  • Temporary credentials with AWS STS
  • Troubleshooting authentication and authorization issues

Time to complete: 10-12 hours
Prerequisites: Chapter 0 (Fundamentals), Chapter 1 (Threat Detection basics)

Why this domain matters: Identity and Access Management is the foundation of AWS security. 16% of the exam tests your ability to design, implement, and troubleshoot authentication and authorization for AWS resources. You must understand how to establish identities, control access through policies, and diagnose access issues.


Section 1: Authentication for AWS Resources

Introduction

The problem: Organizations need to securely verify the identity of users and applications before granting access to AWS resources. Traditional username/password approaches don't scale for enterprise environments with thousands of users, multiple identity sources, and complex access requirements.

The solution: AWS provides multiple authentication mechanisms including IAM users, federated identities, temporary credentials, and multi-factor authentication. These work together to establish trust and verify identity before authorization decisions are made.

Why it's tested: The exam heavily tests your understanding of when to use each authentication method, how to implement federation, and how to troubleshoot authentication failures. You need to know the security implications of each approach.

Core Concepts

IAM Users vs Federated Identities

What they are: IAM users are identities created directly in AWS with long-term credentials (access keys, passwords). Federated identities are external identities (from corporate directories, social providers) that temporarily assume AWS roles without needing IAM users.

Why they exist: Organizations already have identity systems (Active Directory, Okta, Azure AD) managing their users. Creating duplicate IAM users for each person is inefficient, creates security risks (multiple passwords to manage), and doesn't scale. Federation allows using existing identities while maintaining centralized control.

Real-world analogy: Think of a hotel key card system. IAM users are like giving each guest a permanent key they keep forever (inefficient, security risk if lost). Federation is like the hotel issuing temporary key cards that work only during your stay and automatically expire when you check out.

How federation works (Detailed step-by-step):

  1. User authenticates with identity provider (IdP): Employee logs into corporate Active Directory or Okta using their existing username/password. The IdP verifies credentials against its user database.

  2. IdP issues SAML assertion: After successful authentication, the IdP generates a SAML 2.0 assertion (XML document) containing user identity, group memberships, and attributes. This assertion is cryptographically signed by the IdP.

  3. User presents SAML assertion to AWS: The user's browser or application sends the SAML assertion to AWS STS (Security Token Service) via the AssumeRoleWithSAML API call.

  4. AWS validates the assertion: AWS STS verifies the SAML assertion signature using the IdP's public certificate (configured in advance). It checks that the assertion hasn't expired and that the IdP is trusted.

  5. AWS issues temporary credentials: If validation succeeds, STS generates temporary security credentials (access key, secret key, session token) valid for 1-12 hours. These credentials are associated with an IAM role that defines what the user can do.

  6. User accesses AWS resources: The application uses the temporary credentials to make AWS API calls. AWS evaluates the IAM role's policies to determine if each action is allowed.

  7. Credentials expire automatically: When the session duration ends, the credentials become invalid. The user must re-authenticate with the IdP to get new credentials.

📊 SAML Federation Architecture Diagram:

sequenceDiagram
    participant User
    participant Browser
    participant IdP as Identity Provider<br/>(Active Directory/Okta)
    participant STS as AWS STS
    participant AWS as AWS Resources

    User->>Browser: 1. Access AWS Console/App
    Browser->>IdP: 2. Redirect to IdP login
    User->>IdP: 3. Enter credentials
    IdP->>IdP: 4. Validate credentials
    IdP->>Browser: 5. Return SAML assertion (signed)
    Browser->>STS: 6. AssumeRoleWithSAML(assertion)
    STS->>STS: 7. Validate SAML signature
    STS->>Browser: 8. Return temp credentials<br/>(AccessKey, SecretKey, SessionToken)
    Browser->>AWS: 9. API calls with temp credentials
    AWS->>AWS: 10. Evaluate IAM role policies
    AWS->>Browser: 11. Allow/Deny response

    Note over STS,AWS: Credentials expire after 1-12 hours

See: diagrams/05_domain4_saml_federation.mmd

Diagram Explanation (detailed):

This sequence diagram shows the complete SAML federation flow from initial user access through credential issuance to AWS resource access. The process begins when a user attempts to access AWS resources (step 1). Instead of logging in with an IAM user, the browser redirects to the organization's Identity Provider (step 2), which could be Active Directory Federation Services (ADFS), Okta, Azure AD, or another SAML 2.0 compatible system.

The user authenticates with their corporate credentials (step 3), which the IdP validates against its user directory (step 4). This is the only place where the actual password is checked - AWS never sees the user's password. Upon successful authentication, the IdP generates a SAML assertion (step 5), which is an XML document containing the user's identity, group memberships, and other attributes. Critically, this assertion is cryptographically signed using the IdP's private key, ensuring it cannot be tampered with.

The browser then sends this SAML assertion to AWS Security Token Service (STS) via the AssumeRoleWithSAML API (step 6). AWS STS validates the assertion's signature using the IdP's public certificate that was configured in advance (step 7). This verification ensures the assertion genuinely came from the trusted IdP and hasn't been modified. If validation succeeds, STS issues temporary security credentials (step 8) consisting of an access key ID, secret access key, and session token. These credentials are tied to an IAM role that defines the user's permissions.

The application can now use these temporary credentials to make AWS API calls (step 9). For each API call, AWS evaluates the IAM role's policies to determine if the action is permitted (step 10), returning either an allow or deny response (step 11). The temporary credentials automatically expire after the configured session duration (1-12 hours), at which point the user must re-authenticate with the IdP to obtain new credentials. This automatic expiration significantly reduces the risk of credential theft compared to long-term IAM user credentials.

Detailed Example 1: Enterprise Employee Access with IAM Identity Center

A large financial services company has 5,000 employees who need access to AWS resources across 50 AWS accounts. They use Microsoft Active Directory for employee authentication. Here's how they implement federation:

Setup Phase:

  1. Enable AWS IAM Identity Center in the AWS Organizations management account
  2. Connect IAM Identity Center to Active Directory using AD Connector (establishes trust relationship)
  3. Create permission sets in IAM Identity Center (e.g., "Developer", "DataAnalyst", "SecurityAuditor") that define what users can do
  4. Assign Active Directory groups to permission sets for specific AWS accounts (e.g., "Engineering-Team" group gets "Developer" permissions in the Dev account)

Daily Usage:

  1. Employee opens browser and navigates to the AWS access portal URL (e.g., https://mycompany.awsapps.com/start)
  2. IAM Identity Center redirects to Active Directory login page
  3. Employee enters their corporate username/password (same credentials used for email, file shares, etc.)
  4. Active Directory validates credentials and returns SAML assertion to IAM Identity Center
  5. IAM Identity Center displays a portal showing all AWS accounts and applications the employee can access
  6. Employee clicks on "Dev Account - Developer Role"
  7. IAM Identity Center calls STS AssumeRole and returns temporary credentials valid for 8 hours
  8. Employee is logged into AWS Console with Developer permissions
  9. After 8 hours, credentials expire and employee must re-authenticate

Benefits: Single sign-on experience, no IAM users to manage, automatic access removal when employee leaves (removed from AD), centralized audit trail, MFA enforced at AD level.

Detailed Example 2: Mobile App Users with Amazon Cognito

A healthcare startup builds a mobile app for patients to view medical records. They need to authenticate millions of patients and give each patient access only to their own data in DynamoDB. Here's the architecture:

Setup Phase:

  1. Create Amazon Cognito User Pool to store patient identities (email, password, profile)
  2. Configure password policy (minimum 12 characters, require uppercase, numbers, special characters)
  3. Enable MFA using SMS or TOTP authenticator apps
  4. Create Cognito Identity Pool to exchange Cognito tokens for AWS credentials
  5. Create IAM role with policy allowing DynamoDB access only to items where partition key matches user's ID

User Registration Flow:

  1. Patient downloads mobile app and clicks "Sign Up"
  2. App collects email, password, phone number and calls Cognito User Pool CreateUser API
  3. Cognito sends verification code via email
  4. Patient enters code, Cognito marks account as verified
  5. Patient sets up MFA by scanning QR code with authenticator app

Authentication Flow:

  1. Patient opens app and enters email/password
  2. App calls Cognito InitiateAuth API
  3. Cognito validates credentials and prompts for MFA code
  4. Patient enters 6-digit code from authenticator app
  5. Cognito validates MFA and returns ID token, access token, and refresh token
  6. App exchanges Cognito ID token for AWS credentials by calling Cognito Identity Pool
  7. Identity Pool calls STS AssumeRoleWithWebIdentity and returns temporary AWS credentials
  8. App uses credentials to call DynamoDB GetItem with patient's medical record ID
  9. IAM policy ensures patient can only access records where PatientID matches their Cognito user ID

Benefits: Scales to millions of users, built-in MFA, password reset flows, social identity federation (Google, Facebook), fine-grained access control, no need to manage user database.

Detailed Example 3: Cross-Account Access for Third-Party Auditor

A company needs to grant a third-party security auditor read-only access to their AWS accounts for compliance review. They don't want to create IAM users or share long-term credentials.

Setup:

  1. Create IAM role "SecurityAuditorRole" in company's AWS account
  2. Configure trust policy allowing auditor's AWS account to assume the role
  3. Attach ReadOnlyAccess managed policy to the role
  4. Add condition requiring MFA for role assumption
  5. Provide auditor with role ARN and instructions

Auditor Access Flow:

  1. Auditor logs into their own AWS account with IAM user + MFA
  2. Auditor runs AWS CLI command: aws sts assume-role --role-arn arn:aws:iam::123456789012:role/SecurityAuditorRole --role-session-name audit-session --serial-number arn:aws:iam::999999999999:mfa/auditor --token-code 123456
  3. AWS STS validates that auditor's account is trusted and MFA token is correct
  4. STS returns temporary credentials valid for 1 hour
  5. Auditor configures AWS CLI profile with temporary credentials
  6. Auditor runs read-only commands to review security configurations
  7. After 1 hour, credentials expire automatically
  8. All auditor actions are logged in CloudTrail with session name "audit-session"

Benefits: No long-term credentials shared, automatic expiration, MFA required, full audit trail, easy to revoke (delete role), principle of least privilege (read-only).

Must Know (Critical Facts):

  • IAM users have long-term credentials (access keys, passwords) that don't expire automatically. Use only for applications that can't use roles or for emergency break-glass access. Never use for human users in production.

  • Federation uses temporary credentials that automatically expire (1-12 hours). Always prefer federation over IAM users for human access. Reduces risk of credential theft and simplifies user management.

  • AWS STS (Security Token Service) is the service that issues temporary credentials. All federation methods (SAML, OIDC, Web Identity) ultimately call STS APIs like AssumeRole, AssumeRoleWithSAML, or AssumeRoleWithWebIdentity.

  • SAML 2.0 is for enterprise workforce identity (employees accessing AWS). Use with corporate identity providers like Active Directory, Okta, Azure AD. Supports single sign-on and centralized user management.

  • OIDC/Web Identity is for customer/consumer identity (app users, mobile users). Use with Amazon Cognito, Google, Facebook, or other OIDC providers. Scales to millions of users.

  • IAM Identity Center (formerly AWS SSO) is AWS's recommended solution for workforce access to multiple AWS accounts. Provides single sign-on, centralized permission management, and integrates with existing identity providers.

  • Amazon Cognito has two components: User Pools (authentication - verify who you are) and Identity Pools (authorization - exchange tokens for AWS credentials). Often used together but serve different purposes.

  • MFA (Multi-Factor Authentication) adds second factor beyond password. Supports virtual MFA (TOTP apps like Google Authenticator), hardware MFA (YubiKey), and SMS. Required for root user and recommended for all privileged access.

When to use (Comprehensive):

  • Use IAM Identity Center when: You have multiple AWS accounts in AWS Organizations and need to provide workforce users (employees, contractors) with single sign-on access. Best for centralized management of human user access across many accounts.

  • Use SAML federation with IAM when: You have a single AWS account or need custom federation logic not supported by IAM Identity Center. Requires more manual configuration but provides flexibility.

  • Use Amazon Cognito when: Building mobile or web applications that need to authenticate end users (customers, patients, students). Provides user registration, login, password reset, MFA, and social identity federation out of the box.

  • Use IAM roles for EC2/Lambda when: Applications running on AWS compute services need to access other AWS services. Instance profiles automatically provide temporary credentials that rotate every 6 hours.

  • Use cross-account roles when: Resources in one AWS account need to access resources in another account, or when granting third-party access. Eliminates need to share credentials between accounts.

  • Don't use IAM users when: Authenticating human users for regular access. Federation with temporary credentials is more secure. IAM users should be reserved for emergency access, legacy applications, or service accounts that cannot use roles.

  • Don't use long-term access keys when: The application runs on AWS infrastructure (EC2, Lambda, ECS). Use IAM roles instead. Access keys should only be used for applications running outside AWS that cannot assume roles.

  • Don't use root user credentials when: Performing day-to-day operations. Root user has unrestricted access and should only be used for account-level tasks like changing billing information or closing the account. Enable MFA and lock credentials in safe.

Limitations & Constraints:

  • IAM Identity Center requires AWS Organizations: Cannot use in standalone accounts. Must enable Organizations and designate management account.

  • Cognito User Pool limit: 40 million users per user pool. For larger scale, use multiple user pools or consider external identity providers.

  • STS temporary credential duration: Minimum 15 minutes, maximum 12 hours for AssumeRole. Maximum 1 hour for AssumeRoleWithSAML and AssumeRoleWithWebIdentity (unless using chained role sessions).

  • MFA for root user is virtual or hardware only: SMS MFA not supported for root user (only for IAM users). Must use TOTP authenticator app or hardware token.

  • Federation requires trust relationship: Both sides must be configured - IdP must trust AWS (via metadata exchange) and AWS must trust IdP (via SAML provider or OIDC provider configuration).

💡 Tips for Understanding:

  • Think of authentication as "proving who you are" and authorization as "proving what you can do". Authentication happens first (verify identity), then authorization (check permissions).

  • Temporary credentials are always safer than long-term credentials because they automatically expire. Even if stolen, they become useless after expiration.

  • Federation is like a passport system: Your home country (IdP) issues a passport (SAML assertion) that other countries (AWS) accept as proof of identity. You don't need separate citizenship (IAM user) in each country.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking IAM Identity Center and IAM are the same thing

    • Why it's wrong: IAM Identity Center is a separate service built on top of IAM. It provides SSO and centralized permission management across multiple accounts. IAM is the underlying authorization service.
    • Correct understanding: IAM Identity Center uses IAM roles behind the scenes but adds SSO, permission sets, and multi-account management. You can use IAM without Identity Center, but Identity Center always uses IAM.
  • Mistake 2: Believing federated users need IAM users

    • Why it's wrong: The whole point of federation is to avoid creating IAM users. Federated users temporarily assume IAM roles.
    • Correct understanding: Federation exchanges external identity (from IdP) for temporary AWS credentials tied to an IAM role. No IAM user is created or needed.
  • Mistake 3: Confusing Cognito User Pools with Identity Pools

    • Why it's wrong: They serve different purposes and are often used together but are separate services.
    • Correct understanding: User Pools handle authentication (login, registration, password management). Identity Pools handle authorization (exchange tokens for AWS credentials). User Pool authenticates user → returns JWT token → Identity Pool exchanges JWT for AWS credentials.

🔗 Connections to Other Topics:

  • Relates to CloudTrail (Domain 2) because: All authentication events (successful logins, failed attempts, role assumptions) are logged in CloudTrail. Essential for security auditing and incident response.

  • Builds on IAM Roles (this chapter) by: Federation uses IAM roles as the target for temporary credential issuance. The role's policies determine what the federated user can do.

  • Often used with Multi-Account Strategy (Domain 6) to: Provide single sign-on across many AWS accounts using IAM Identity Center. Users authenticate once and can access multiple accounts based on permission sets.


Section 2: Authorization with IAM Policies

Introduction

The problem: After authenticating a user (proving who they are), AWS needs to determine what actions they're allowed to perform on which resources. Without a flexible authorization system, you'd need to hardcode permissions into applications or create separate accounts for each permission level.

The solution: IAM policies are JSON documents that define permissions. They specify which actions are allowed or denied on which resources under what conditions. Policies can be attached to identities (users, groups, roles) or resources (S3 buckets, KMS keys) to control access.

Why it's tested: The exam extensively tests your ability to write, interpret, and troubleshoot IAM policies. You must understand policy evaluation logic, different policy types, and how to apply the principle of least privilege. Many exam questions present scenarios requiring you to choose the correct policy or diagnose why access is denied.

Core Concepts

IAM Policy Types and Evaluation

What they are: AWS supports seven types of policies that work together to determine if an action is allowed. Each policy type serves a different purpose and is evaluated in a specific order.

Why they exist: Different policy types solve different problems. Identity-based policies grant permissions to users/roles. Resource-based policies grant permissions to resources. Permissions boundaries limit maximum permissions. SCPs enforce organizational guardrails. This layered approach provides flexibility while maintaining security.

Real-world analogy: Think of policy types like security clearance levels in a government building. Your badge (identity-based policy) grants you access to certain floors. Each room has its own lock (resource-based policy) that may further restrict access. Your department has maximum clearance levels (permissions boundary) you can't exceed. The building has overall rules (SCPs) that apply to everyone regardless of clearance.

How policy evaluation works (Detailed step-by-step):

  1. Default Deny: By default, all requests are denied. AWS uses an explicit allow model - you must explicitly grant permissions.

  2. Evaluate all applicable policies: AWS collects all policies that apply to the request - identity-based policies attached to the user/role, resource-based policies on the target resource, permissions boundaries, SCPs, session policies.

  3. Check for explicit deny: AWS scans all policies for explicit Deny statements. If any policy explicitly denies the action, the request is immediately denied. Explicit denies always win, regardless of any allows.

  4. Check for explicit allow: If no explicit deny exists, AWS looks for explicit Allow statements. The action must be explicitly allowed by at least one policy.

  5. Apply permissions boundaries: If the identity has a permissions boundary, the action must be allowed by both the identity-based policy AND the permissions boundary. The boundary acts as a filter - it can only restrict, never expand permissions.

  6. Apply SCPs: If the account is in an AWS Organization, the action must be allowed by all applicable SCPs (at account level, OU level, organization level). SCPs act as guardrails - they can only restrict, never grant permissions.

  7. Final decision: The request is allowed only if it passes all checks - no explicit deny, at least one explicit allow, within permissions boundary (if set), within SCP limits (if applicable).

📊 IAM Policy Evaluation Logic Diagram:

graph TD
    A[Request Made] --> B{Explicit Deny<br/>in any policy?}
    B -->|Yes| Z[❌ DENY]
    B -->|No| C{Explicit Allow<br/>in identity-based<br/>or resource-based?}
    C -->|No| Z
    C -->|Yes| D{Permissions<br/>Boundary set?}
    D -->|No| E{Account in<br/>Organization?}
    D -->|Yes| F{Allow in<br/>Boundary?}
    F -->|No| Z
    F -->|Yes| E
    E -->|No| Y[✅ ALLOW]
    E -->|Yes| G{Allow in<br/>all SCPs?}
    G -->|No| Z
    G -->|Yes| Y

    style Z fill:#ffebee
    style Y fill:#c8e6c9
    style B fill:#fff3e0
    style C fill:#fff3e0
    style F fill:#fff3e0
    style G fill:#fff3e0

See: diagrams/05_domain4_policy_evaluation.mmd

Diagram Explanation (detailed):

This decision tree shows the complete IAM policy evaluation logic that AWS uses for every API request. The evaluation follows a specific order designed to prioritize security (denies) over convenience (allows).

The process starts when any request is made to AWS (step A). The first check (step B) scans ALL applicable policies for explicit Deny statements. This includes identity-based policies, resource-based policies, permissions boundaries, SCPs, and session policies. If ANY policy contains an explicit deny for this action, the request is immediately rejected (path to Z). This is the most important rule: explicit denies always win. You cannot override a deny with an allow from another policy.

If no explicit deny exists, AWS checks for explicit Allow statements (step C). The request must be explicitly allowed by at least one of the following: an identity-based policy attached to the user/role, OR a resource-based policy on the target resource. If neither type of policy allows the action, the request is denied by default (path to Z). This is AWS's "default deny" principle - everything is denied unless explicitly allowed.

If an explicit allow exists, AWS then checks if a permissions boundary is set on the identity (step D). Permissions boundaries are optional - they're only used when you want to limit the maximum permissions an identity can have. If no boundary is set, evaluation continues to SCP check (step E). If a boundary IS set (step F), the action must also be allowed by the permissions boundary policy. The boundary acts as a filter - even if the identity-based policy allows the action, the boundary can block it. If the boundary doesn't allow it, the request is denied (path to Z).

Finally, if the AWS account is part of an AWS Organization (step E), AWS checks all applicable Service Control Policies (step G). SCPs are applied at the organization, OU, and account levels. The action must be allowed by ALL applicable SCPs in the hierarchy. If any SCP denies or doesn't allow the action, the request is denied (path to Z). SCPs act as guardrails that apply to all principals in the account, including the account root user.

Only if the request passes all these checks - no explicit deny, at least one explicit allow, within permissions boundary (if set), and within SCP limits (if applicable) - is the request finally allowed (path to Y). This multi-layered evaluation ensures security by requiring multiple affirmative checks while allowing any single deny to block access.

Identity-Based vs Resource-Based Policies

What they are: Identity-based policies are attached to IAM identities (users, groups, roles) and define what those identities can do. Resource-based policies are attached to AWS resources (S3 buckets, KMS keys, Lambda functions) and define who can access those resources.

Why both exist: Identity-based policies are great for managing permissions for users and roles. But sometimes you need to grant access to a resource from multiple accounts or services. Resource-based policies make this easier by centralizing permissions on the resource itself.

Real-world analogy: Identity-based policies are like employee badges that grant access to certain rooms. Resource-based policies are like locks on specific rooms that specify which badges can open them. Sometimes you need both - your badge must allow access AND the room's lock must accept your badge.

How they work together (Detailed step-by-step):

  1. Same-account access: If the principal (user/role) and resource are in the same account, you need EITHER an identity-based policy OR a resource-based policy to allow access. One explicit allow is sufficient.

  2. Cross-account access: If the principal and resource are in different accounts, you need BOTH an identity-based policy (in the principal's account) AND a resource-based policy (on the resource) to allow access. Both must explicitly allow the action.

  3. Policy evaluation: AWS evaluates all applicable policies together. An explicit deny in any policy overrides all allows. If no explicit deny exists, at least one explicit allow is required.

Detailed Example 1: S3 Bucket Access - Same Account

A Lambda function in account 111111111111 needs to read objects from an S3 bucket in the same account. You have two options:

Option A - Identity-Based Policy Only:
Attach this policy to the Lambda function's execution role:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetObject",
        "s3:ListBucket"
      ],
      "Resource": [
        "arn:aws:s3:::my-bucket",
        "arn:aws:s3:::my-bucket/*"
      ]
    }
  ]
}

No bucket policy needed. The identity-based policy alone grants access.

Option B - Resource-Based Policy Only:
Attach this bucket policy to the S3 bucket:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::111111111111:role/LambdaExecutionRole"
      },
      "Action": [
        "s3:GetObject",
        "s3:ListBucket"
      ],
      "Resource": [
        "arn:aws:s3:::my-bucket",
        "arn:aws:s3:::my-bucket/*"
      ]
    }
  ]
}

No identity-based policy needed. The bucket policy alone grants access.

Best Practice: Use identity-based policies for same-account access. They're easier to manage and audit. Use resource-based policies when you need to grant access from multiple principals or accounts.

Detailed Example 2: S3 Bucket Access - Cross-Account

A Lambda function in account 111111111111 needs to read objects from an S3 bucket in account 222222222222. You need BOTH policies:

Identity-Based Policy (attached to Lambda role in account 111111111111):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetObject",
        "s3:ListBucket"
      ],
      "Resource": [
        "arn:aws:s3:::cross-account-bucket",
        "arn:aws:s3:::cross-account-bucket/*"
      ]
    }
  ]
}

Resource-Based Policy (bucket policy in account 222222222222):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::111111111111:role/LambdaExecutionRole"
      },
      "Action": [
        "s3:GetObject",
        "s3:ListBucket"
      ],
      "Resource": [
        "arn:aws:s3:::cross-account-bucket",
        "arn:aws:s3:::cross-account-bucket/*"
      ]
    }
  ]
}

Both policies must explicitly allow the action. If either policy is missing or denies the action, access is denied.

Detailed Example 3: KMS Key Access - Cross-Account Encryption

Account 111111111111 has an S3 bucket with objects encrypted using a KMS key in account 222222222222. For Lambda in account 111111111111 to decrypt objects, you need THREE policies:

1. Identity-Based Policy (Lambda role in account 111111111111):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:GetObject",
        "kms:Decrypt"
      ],
      "Resource": [
        "arn:aws:s3:::encrypted-bucket/*",
        "arn:aws:kms:us-east-1:222222222222:key/12345678-1234-1234-1234-123456789012"
      ]
    }
  ]
}

2. S3 Bucket Policy (in account 111111111111):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::111111111111:role/LambdaExecutionRole"
      },
      "Action": "s3:GetObject",
      "Resource": "arn:aws:s3:::encrypted-bucket/*"
    }
  ]
}

3. KMS Key Policy (in account 222222222222):

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::111111111111:role/LambdaExecutionRole"
      },
      "Action": "kms:Decrypt",
      "Resource": "*"
    }
  ]
}

All three policies must allow the actions. This is a common exam scenario - cross-account access with encryption requires policies in both accounts.

Permissions Boundaries - Maximum Permission Limits

What they are: A permissions boundary is a managed policy that sets the maximum permissions an IAM entity (user or role) can have. The entity can only perform actions that are allowed by BOTH its identity-based policies AND its permissions boundary.

Why they exist: Permissions boundaries solve the delegation problem. You want to allow developers to create IAM roles for their applications, but you don't want them to create roles with more permissions than they have themselves (privilege escalation). Permissions boundaries enforce maximum permission limits.

Real-world analogy: A permissions boundary is like a spending limit on a corporate credit card. Your manager might approve specific purchases (identity-based policies), but the card has a maximum limit (permissions boundary) that cannot be exceeded regardless of approvals.

How permissions boundaries work (Detailed step-by-step):

  1. Boundary Attachment: You attach a managed policy as a permissions boundary to an IAM user or role. This is separate from attaching identity-based policies.

  2. Policy Evaluation: When the user/role makes a request, AWS evaluates both the identity-based policies and the permissions boundary.

  3. Intersection Logic: The effective permissions are the intersection of identity-based policies and the permissions boundary. An action is allowed only if BOTH allow it.

  4. Deny Override: An explicit deny in any policy (identity-based, boundary, SCP) overrides all allows.

  5. No Permission Grant: Permissions boundaries do NOT grant permissions. They only limit permissions. You still need identity-based policies to grant permissions.

Detailed Example 1: Developer Self-Service IAM Role Creation

A company wants to allow developers to create IAM roles for their Lambda functions, but prevent them from creating roles with admin access. Here's how they use permissions boundaries:

Step 1 - Create Permissions Boundary Policy:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "s3:*",
        "dynamodb:*",
        "lambda:*",
        "logs:*",
        "cloudwatch:*"
      ],
      "Resource": "*"
    },
    {
      "Effect": "Deny",
      "Action": [
        "iam:*",
        "organizations:*",
        "account:*"
      ],
      "Resource": "*"
    }
  ]
}

This boundary allows common application services but denies IAM, Organizations, and account management.

Step 2 - Grant Developers IAM Role Creation Permission:
Attach this policy to the developer role:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "iam:CreateRole",
        "iam:AttachRolePolicy",
        "iam:PutRolePermissionsBoundary"
      ],
      "Resource": "*",
      "Condition": {
        "StringEquals": {
          "iam:PermissionsBoundary": "arn:aws:iam::123456789012:policy/DeveloperBoundary"
        }
      }
    }
  ]
}

This allows developers to create roles ONLY if they attach the DeveloperBoundary permissions boundary.

Step 3 - Developer Creates Role:
Developer creates a Lambda execution role:

aws iam create-role \
  --role-name MyLambdaRole \
  --assume-role-policy-document file://trust-policy.json \
  --permissions-boundary arn:aws:iam::123456789012:policy/DeveloperBoundary

Developer attaches a policy granting full admin access:

aws iam attach-role-policy \
  --role-name MyLambdaRole \
  --policy-arn arn:aws:iam::aws:policy/AdministratorAccess

Step 4 - Effective Permissions:
Even though the role has AdministratorAccess policy attached, the permissions boundary limits it. The role can only perform actions allowed by BOTH policies:

  • ✅ Can access S3, DynamoDB, Lambda (allowed by both)
  • ❌ Cannot manage IAM (denied by boundary)
  • ❌ Cannot manage Organizations (denied by boundary)

Result: Developers can create roles for their applications without risk of privilege escalation. The permissions boundary enforces maximum permission limits.

Must Know (Critical Facts):

  • Policy evaluation follows explicit deny > explicit allow logic: An explicit deny in any policy always wins. If no explicit deny, you need at least one explicit allow. Default is deny.

  • Seven policy types exist: Identity-based, resource-based, permissions boundaries, SCPs, RCPs, ACLs, and session policies. Each serves a different purpose and is evaluated differently.

  • Cross-account access requires policies in both accounts: The principal's account needs an identity-based policy allowing the action. The resource's account needs a resource-based policy allowing the principal.

  • Permissions boundaries do NOT grant permissions: They only limit maximum permissions. You still need identity-based policies to grant permissions. Boundaries are useful for delegation scenarios.

  • SCPs apply to all principals in an account: Including the root user. They set maximum permissions for the entire account. Cannot be bypassed by any identity-based or resource-based policy.

  • Resource-based policies specify a Principal: This is how you grant cross-account access. The Principal element identifies who can access the resource (account, user, role, service).

  • IAM policy simulator tests policy evaluation: Use it to test whether a specific action would be allowed or denied given a set of policies. Essential for troubleshooting access issues.

  • Condition elements add context-based restrictions: You can require MFA, restrict by IP address, enforce encryption, limit by time of day, and more. Conditions make policies more secure and flexible.

When to use (Comprehensive):

  • Use identity-based policies when: Granting permissions to users, groups, or roles within your account. Easiest to manage and audit. Preferred for same-account access.

  • Use resource-based policies when: Granting cross-account access, allowing AWS services to access resources, or centralizing permissions on the resource. Required for cross-account access to S3, KMS, Lambda, etc.

  • Use permissions boundaries when: Delegating IAM role/user creation to developers or teams. Prevents privilege escalation by enforcing maximum permission limits.

  • Use SCPs when: Enforcing organizational guardrails across multiple accounts. Prevents accounts from using specific services or regions. Applied at organization, OU, or account level.

  • Use session policies when: Temporarily restricting permissions when assuming a role or federating. Useful for limiting permissions for specific sessions without modifying the role's policies.

  • Use IAM policy simulator when: Testing policy changes before applying them, troubleshooting access denied errors, or validating that policies grant expected permissions.

  • Don't use inline policies for policies shared across multiple identities. Use managed policies instead. Inline policies are harder to manage and audit.

  • Don't grant more permissions than needed (principle of least privilege). Start with minimal permissions and add as needed. Overly permissive policies increase security risk.

  • Don't forget to test cross-account access in both accounts. A common mistake is configuring the resource-based policy but forgetting the identity-based policy (or vice versa).

Limitations & Constraints:

  • Policy size limits: Identity-based policies: 2KB (inline), 6KB (managed). Resource-based policies vary by service (S3: 20KB, KMS: 32KB). Large policies may need to be split.

  • Policy evaluation is complex: With multiple policy types (identity-based, resource-based, SCPs, permissions boundaries), determining effective permissions requires understanding evaluation logic. Use IAM policy simulator to test.

  • Cross-account access requires coordination: Both accounts must configure policies correctly. Common mistake is configuring only one side. Always test cross-account access after setup.

  • SCPs don't grant permissions: SCPs only restrict permissions. You still need identity-based policies to grant permissions. SCPs set maximum allowed permissions.

💡 Tips for Understanding:

  • Think of permissions boundaries as a "permission ceiling": No matter what identity-based policies grant, the boundary limits maximum permissions. Useful for delegating IAM administration safely.

  • Remember the policy evaluation mantra: "Explicit deny > Explicit allow > Default deny". An explicit deny always wins. If no explicit deny, you need at least one explicit allow. Default is deny.

  • Use IAM policy simulator for troubleshooting: When access is denied unexpectedly, use the simulator to test which policy is causing the denial. It shows the evaluation logic step-by-step.

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Forgetting to configure both sides for cross-account access

    • Why it's wrong: Cross-account access requires policies in both accounts. The principal's account needs an identity-based policy allowing the action. The resource's account needs a resource-based policy allowing the principal.
    • Correct understanding: Always configure both sides. Use IAM policy simulator to test cross-account access before deploying to production.
  • Mistake 2: Thinking permissions boundaries grant permissions

    • Why it's wrong: Permissions boundaries only limit maximum permissions. They don't grant any permissions. You still need identity-based policies to grant permissions.
    • Correct understanding: Permissions boundaries are a safety mechanism. They prevent privilege escalation by enforcing maximum permission limits. Use them when delegating IAM administration.
  • Mistake 3: Believing SCPs apply only to IAM users

    • Why it's wrong: SCPs apply to all principals in an account, including the root user, IAM users, IAM roles, and federated users. Only the management account root user is exempt.
    • Correct understanding: SCPs are organizational guardrails that apply to entire accounts. Use them to enforce security policies across all accounts in your organization.

🔗 Connections to Other Topics:

  • Relates to CloudTrail (Domain 2) because: CloudTrail logs all IAM API calls, which is essential for auditing who did what and when. Use CloudTrail to investigate unauthorized access or policy changes.

  • Builds on Incident Response (Domain 1) by: Providing credential invalidation and rotation mechanisms. When credentials are compromised, use IAM to disable access keys, reset passwords, and rotate credentials.

  • Often used with Data Protection (Domain 5) to: Control access to encrypted data. KMS key policies (resource-based policies) determine who can use encryption keys. IAM policies determine who can call KMS APIs.


Chapter Summary

What We Covered

  • Authentication: IAM users, roles, federated identities, MFA, temporary credentials with STS
  • Authorization: IAM policies (identity-based, resource-based, permissions boundaries, SCPs), policy evaluation logic
  • Policy Types: Seven policy types and when to use each
  • Cross-Account Access: How to configure trust relationships and policies in both accounts
  • Troubleshooting: Using IAM policy simulator, CloudTrail, and IAM Access Advisor

Critical Takeaways

  1. Policy Evaluation Logic: Explicit deny > Explicit allow > Default deny. An explicit deny always wins. If no explicit deny, you need at least one explicit allow. Default is deny.

  2. Cross-Account Access Requires Both Sides: The principal's account needs an identity-based policy allowing the action. The resource's account needs a resource-based policy allowing the principal. Both are required.

  3. Permissions Boundaries Don't Grant Permissions: They only limit maximum permissions. You still need identity-based policies to grant permissions. Use boundaries for delegation scenarios.

  4. SCPs Apply to All Principals: Including the root user (except management account root user). SCPs set maximum permissions for entire accounts. Cannot be bypassed.

  5. Temporary Credentials are Preferred: Use IAM roles with temporary credentials instead of long-term access keys. Temporary credentials automatically expire and rotate.

  6. MFA Adds Critical Protection: Require MFA for privileged operations. Use MFA condition in IAM policies to enforce MFA for sensitive actions.

  7. IAM Policy Simulator Tests Policies: Use the simulator to test policy changes before applying them. It shows which policies allow or deny specific actions.

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between authentication and authorization
  • I understand how IAM roles provide temporary credentials
  • I can describe the policy evaluation logic (explicit deny > explicit allow > default deny)
  • I know when to use identity-based vs. resource-based policies
  • I can configure cross-account access with trust relationships
  • I understand how permissions boundaries limit maximum permissions
  • I know how SCPs enforce organizational guardrails
  • I can use IAM policy simulator to troubleshoot access issues
  • I understand when to use STS to issue temporary credentials
  • I can design ABAC and RBAC authorization strategies

If you answered "no" to any of these, review the relevant section before proceeding.

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-40 (IAM fundamentals)
  • Domain 4 Bundle 2: Questions 41-80 (Advanced IAM and troubleshooting)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections on policy evaluation logic and policy types
  • Focus on understanding cross-account access configuration
  • Practice distinguishing between policy types (identity-based, resource-based, SCPs, permissions boundaries)
  • Review troubleshooting methodologies using IAM policy simulator

Quick Reference Card

Authentication Methods:

  • IAM Users: Long-term credentials (password, access keys)
  • IAM Roles: Temporary credentials (assumed by users, services, or applications)
  • Federated Identities: External identity providers (SAML, OIDC)
  • MFA: Additional authentication factor (virtual MFA, hardware token, U2F)

Policy Types:

  • Identity-based: Attached to users, groups, roles (managed or inline)
  • Resource-based: Attached to resources (S3, KMS, Lambda, etc.)
  • Permissions Boundaries: Limit maximum permissions for users/roles
  • SCPs: Organizational guardrails (apply to accounts)
  • Session Policies: Temporary restrictions when assuming roles
  • ACLs: Legacy access control (S3, VPC)
  • RCPs: Resource Control Policies (AWS RAM)

Policy Evaluation:

  1. Explicit Deny → Always deny (highest priority)
  2. Explicit Allow → Allow if no explicit deny
  3. Default Deny → Deny if no explicit allow (lowest priority)

Cross-Account Access:

  1. Resource account: Create resource-based policy allowing principal
  2. Principal account: Create identity-based policy allowing action
  3. Test: Use IAM policy simulator to verify access

Troubleshooting Tools:

  • IAM Policy Simulator: Test policy evaluation before applying
  • CloudTrail: Audit IAM API calls and access attempts
  • IAM Access Advisor: See which services were accessed and when
  • IAM Access Analyzer: Identify resources shared with external entities

Decision Points:

  • Same-account access → Identity-based policies
  • Cross-account access → Resource-based policies + identity-based policies
  • Delegate IAM administration → Permissions boundaries
  • Organizational guardrails → SCPs
  • Temporary access → IAM roles with STS
  • External identities → Federated identities (SAML, OIDC)
  • Troubleshoot access denied → IAM policy simulator

Chapter 4 Complete

Next Chapter: 06_domain5_data_protection - Data Protection (18% of exam)


Section 3: Advanced IAM Concepts - ABAC, RBAC, and Policy Types

Introduction

The problem: As AWS environments grow, managing permissions becomes complex. Traditional role-based access control (RBAC) requires creating many roles for different scenarios. Permissions boundaries, service control policies, and session policies add layers of complexity. Without understanding these advanced concepts, organizations struggle to implement least privilege at scale.

The solution: AWS provides multiple policy types and access control strategies to manage permissions at scale. Attribute-based access control (ABAC) uses tags to dynamically grant permissions. Permissions boundaries limit maximum permissions. Service control policies (SCPs) provide organizational guardrails. Understanding these concepts enables scalable, secure access management.

Why it's tested: Advanced IAM concepts are critical for the Security Specialty exam. The exam tests your ability to design ABAC strategies, implement permissions boundaries, troubleshoot complex policy interactions, and apply least privilege principles at scale.

Core Concepts

Attribute-Based Access Control (ABAC) - Tag-Based Permissions

What it is: ABAC is an authorization strategy that grants permissions based on attributes (tags) rather than explicit resource ARNs. Instead of creating separate policies for each resource, you create a single policy that grants access to resources with matching tags.

Why it exists: Traditional RBAC requires creating and maintaining many roles and policies as resources grow. ABAC scales better by using tags to dynamically determine access. When a new resource is created with the appropriate tags, users automatically get access without policy updates.

Real-world analogy: ABAC is like a building access system that grants entry based on employee attributes (department, clearance level) rather than explicit room lists. When a new room is added to the "Engineering" department, all engineers automatically get access without updating the access list.

How it works (Detailed step-by-step):

  1. Tag Resources: You tag AWS resources with attributes like Project, Environment, Owner, Department.
  2. Tag Principals: You tag IAM users and roles with the same attribute keys.
  3. Create ABAC Policy: You create an IAM policy that grants access to resources where tags match the principal's tags.
  4. Policy Evaluation: When a user attempts an action, IAM compares the user's tags with the resource's tags.
  5. Access Decision: If tags match the policy conditions, access is granted. If not, access is denied.
  6. Dynamic Scaling: When new resources are created with appropriate tags, users automatically get access without policy changes.

📊 ABAC vs RBAC Comparison Diagram:

graph TB
    subgraph "RBAC - Role-Based Access Control"
        User1[User: Alice]
        Role1[Role: ProjectA-Developer]
        Policy1[Policy: Allow access to<br/>arn:aws:s3:::projecta-bucket/*<br/>arn:aws:dynamodb:*/table/projecta-*]
        
        User1 --> Role1
        Role1 --> Policy1
        
        Note1[❌ Must update policy<br/>for each new resource]
    end
    
    subgraph "ABAC - Attribute-Based Access Control"
        User2[User: Bob<br/>Tag: Project=ProjectB]
        Role2[Role: Developer]
        Policy2[Policy: Allow access to resources<br/>WHERE resource tag Project<br/>MATCHES user tag Project]
        Resource1[S3 Bucket<br/>Tag: Project=ProjectB]
        Resource2[DynamoDB Table<br/>Tag: Project=ProjectB]
        
        User2 --> Role2
        Role2 --> Policy2
        Policy2 -.->|Tag Match| Resource1
        Policy2 -.->|Tag Match| Resource2
        
        Note2[✅ Automatic access<br/>to tagged resources]
    end
    
    style Policy2 fill:#c8e6c9
    style Policy1 fill:#ffebee
    style Note2 fill:#c8e6c9
    style Note1 fill:#ffebee

See: diagrams/05_domain4_abac_vs_rbac.mmd

Diagram Explanation (Detailed):

The diagram compares RBAC and ABAC access control strategies. In RBAC (top), User Alice assumes the ProjectA-Developer role, which has a policy explicitly listing resource ARNs (S3 bucket projecta-bucket and DynamoDB tables with projecta- prefix). When a new resource is created for ProjectA, the policy must be manually updated to include the new resource ARN. This doesn't scale well as resources grow. In ABAC (bottom), User Bob is tagged with Project=ProjectB and assumes a generic Developer role. The role's policy grants access to resources WHERE the resource's Project tag MATCHES the user's Project tag. The S3 bucket and DynamoDB table are both tagged with Project=ProjectB, so Bob automatically gets access. When a new resource is created with Project=ProjectB tag, Bob automatically gets access without any policy updates. ABAC scales better because permissions are determined dynamically based on tags rather than explicit resource lists. The policy is written once and works for all current and future resources with matching tags.

Detailed Example 1: Implementing ABAC for Multi-Project Environment

A company has 50 projects, each with multiple developers. Here's how they use ABAC: (1) They tag all IAM users with their assigned project: Project=ProjectA, Project=ProjectB, etc. (2) They tag all AWS resources (S3 buckets, EC2 instances, DynamoDB tables) with the project they belong to. (3) They create a single "Developer" role with an ABAC policy:

{
  "Version": "2012-10-17",
  "Statement": [{
    "Effect": "Allow",
    "Action": ["s3:*", "ec2:*", "dynamodb:*"],
    "Resource": "*",
    "Condition": {
      "StringEquals": {
        "aws:ResourceTag/Project": "${aws:PrincipalTag/Project}"
      }
    }
  }]
}

(4) A developer tagged with Project=ProjectA assumes the Developer role. (5) The developer attempts to access an S3 bucket tagged with Project=ProjectA. (6) IAM evaluates the condition: resource tag Project (ProjectA) matches principal tag Project (ProjectA). (7) Access is granted. (8) The developer attempts to access an S3 bucket tagged with Project=ProjectB. (9) IAM evaluates the condition: resource tag Project (ProjectB) does NOT match principal tag Project (ProjectA). (10) Access is denied. (11) A new S3 bucket is created for ProjectA with the appropriate tag. (12) The developer automatically gets access without any policy updates. ABAC enabled scalable access control across 50 projects with a single policy.

Detailed Example 2: ABAC with Environment Isolation

A company wants to ensure developers can only access development resources, not production. Here's how they use ABAC: (1) They tag all IAM users with their allowed environment: Environment=dev for developers, Environment=prod for operations. (2) They tag all AWS resources with their environment: Environment=dev or Environment=prod. (3) They create an ABAC policy that grants access only to resources with matching environment tags. (4) A developer tagged with Environment=dev attempts to access a development EC2 instance tagged with Environment=dev. (5) Access is granted because tags match. (6) The same developer attempts to access a production EC2 instance tagged with Environment=prod. (7) Access is denied because tags don't match. (8) This prevents developers from accidentally (or intentionally) accessing production resources. (9) Operations staff tagged with Environment=prod can access production resources. (10) The company achieves environment isolation using tags. ABAC enforced environment boundaries without complex policy management.

Detailed Example 3: ABAC with Session Tags for Temporary Access

A company wants to grant temporary project access to contractors. Here's how they use ABAC with session tags: (1) They create a "Contractor" role that contractors can assume. (2) The role has an ABAC policy granting access to resources with matching Project tags. (3) When a contractor needs access to ProjectC, an administrator uses STS AssumeRole with session tags: --tags Key=Project,Value=ProjectC. (4) The contractor assumes the role with the session tag Project=ProjectC. (5) The contractor can now access resources tagged with Project=ProjectC. (6) After the session expires (e.g., 12 hours), the contractor loses access. (7) To grant access to a different project, the administrator issues a new session with a different tag. (8) No policy changes are needed to grant or revoke access. (9) Session tags provide temporary, dynamic access control. ABAC with session tags enabled flexible, temporary access without policy modifications.

Must Know (Critical Facts):

  • ABAC uses tags to dynamically grant permissions based on attribute matching
  • Principal tags (on users/roles) are compared with resource tags using condition keys
  • Session tags can be passed during AssumeRole for temporary attribute-based access
  • ABAC scales better than RBAC because policies don't need updates when resources are added
  • ABAC requires consistent tagging strategy across all resources
  • Condition keys for ABAC: aws:PrincipalTag/key, aws:ResourceTag/key, aws:RequestTag/key
  • ABAC works with all AWS services that support resource tagging

When to use (Comprehensive):

  • ✅ Use ABAC when: You have many resources and users with similar access patterns
  • ✅ Use ABAC when: Resources are frequently created and deleted (dynamic environments)
  • ✅ Use ABAC when: You want to reduce policy management overhead
  • ✅ Use ABAC when: You need to enforce project, environment, or department boundaries
  • ✅ Use ABAC when: You want to grant temporary access based on attributes (session tags)
  • ❌ Don't use ABAC when: You have a small, static environment (RBAC is simpler)
  • ❌ Don't use ABAC when: Your organization lacks a consistent tagging strategy
  • ❌ Don't use ABAC when: You need very granular, resource-specific permissions

Permissions Boundaries - Limiting Maximum Permissions

What it is: A permissions boundary is an IAM policy that sets the maximum permissions an IAM entity (user or role) can have. Even if an identity-based policy grants broader permissions, the permissions boundary limits what actions can actually be performed.

Why it exists: In delegated administration scenarios, you want to allow administrators to create users and roles without giving them the ability to escalate privileges. Permissions boundaries ensure that even if an administrator grants excessive permissions, the boundary limits what can actually be done.

Real-world analogy: A permissions boundary is like a spending limit on a credit card. Even if a merchant tries to charge $10,000, the transaction is declined if your limit is $5,000. The boundary sets the maximum, regardless of what's requested.

How it works (Detailed step-by-step):

  1. Boundary Definition: You create an IAM policy defining the maximum allowed permissions.
  2. Boundary Attachment: You attach the permissions boundary to an IAM user or role.
  3. Policy Evaluation: When the user/role attempts an action, IAM evaluates both the identity-based policy and the permissions boundary.
  4. Effective Permissions: The effective permissions are the intersection of the identity-based policy and the permissions boundary.
  5. Privilege Escalation Prevention: Even if an administrator grants broad permissions, the boundary prevents actions outside the boundary.

📊 Permissions Boundary Diagram:

graph TB
    subgraph "IAM User: Developer"
        IdentityPolicy[Identity-Based Policy<br/>Allow: s3:*, ec2:*, iam:*]
        Boundary[Permissions Boundary<br/>Allow: s3:*, ec2:*<br/>Deny: iam:*]
    end
    
    subgraph "Effective Permissions"
        Effective[Intersection of Policies<br/>Allow: s3:*, ec2:*<br/>Deny: iam:*]
    end
    
    Action1[Action: s3:PutObject]
    Action2[Action: ec2:RunInstances]
    Action3[Action: iam:CreateUser]
    
    IdentityPolicy --> Effective
    Boundary --> Effective
    
    Effective -->|✅ Allowed| Action1
    Effective -->|✅ Allowed| Action2
    Effective -->|❌ Denied| Action3
    
    style Effective fill:#c8e6c9
    style Action3 fill:#ffebee
    style Action1 fill:#c8e6c9
    style Action2 fill:#c8e6c9

See: diagrams/05_domain4_permissions_boundary.mmd

Diagram Explanation (Detailed):

The diagram shows how permissions boundaries limit effective permissions. The IAM user "Developer" has an identity-based policy granting broad permissions: s3:, ec2:, and iam:. However, a permissions boundary is attached that only allows s3: and ec2:, explicitly denying iam:. The effective permissions are the intersection of the identity-based policy and the permissions boundary. The user can perform s3:PutObject (allowed by both policies) and ec2:RunInstances (allowed by both policies). However, the user cannot perform iam:CreateUser because the permissions boundary denies it, even though the identity-based policy allows it. This prevents privilege escalation - even if an administrator grants excessive permissions, the boundary ensures IAM actions are blocked. Permissions boundaries are essential for delegated administration where you want to allow creating users/roles without risking privilege escalation.

Detailed Example 1: Delegated IAM Administration with Permissions Boundaries

A company wants to allow team leads to create IAM users for their teams without risking privilege escalation. Here's how they use permissions boundaries: (1) They create a permissions boundary policy that allows S3, EC2, and DynamoDB actions but denies IAM actions. (2) They create a "TeamLead" role with permissions to create IAM users, but only if a permissions boundary is attached. (3) The policy includes a condition: "Condition": {"StringEquals": {"iam:PermissionsBoundary": "arn:aws:iam::123456789012:policy/TeamBoundary"}}. (4) A team lead assumes the TeamLead role and creates a new IAM user for a developer. (5) The team lead attaches a policy granting s3:, ec2:, and iam:* to the new user. (6) The team lead also attaches the TeamBoundary permissions boundary (required by the condition). (7) The new developer user attempts to create another IAM user (iam:CreateUser). (8) The action is denied because the permissions boundary blocks IAM actions. (9) The developer can use S3 and EC2 as intended. (10) The company achieved delegated administration without privilege escalation risk. Permissions boundaries enabled safe delegation of IAM administration.

Detailed Example 2: Preventing Privilege Escalation

An attacker compromises an IAM user with permissions to modify their own policies. Here's how permissions boundaries prevent escalation: (1) The IAM user has a permissions boundary attached that allows only S3 and EC2 actions. (2) The user's identity-based policy allows s3:* and iam:PutUserPolicy (to update their own policy). (3) The attacker attempts to grant themselves admin permissions by updating the identity-based policy to allow :. (4) The policy update succeeds (iam:PutUserPolicy is allowed). (5) The attacker attempts to perform iam:CreateUser. (6) The action is denied because the permissions boundary blocks IAM actions. (7) Even though the identity-based policy now allows :, the permissions boundary limits effective permissions. (8) The attacker cannot escalate privileges beyond the boundary. (9) Security monitoring detects the suspicious policy modification. (10) The compromised user is disabled. Permissions boundaries prevented privilege escalation even after policy modification.

Must Know (Critical Facts):

  • Permissions boundaries set the maximum permissions, not the granted permissions
  • Effective permissions = intersection of identity-based policy AND permissions boundary
  • Permissions boundaries do NOT grant permissions - they only limit them
  • Permissions boundaries can be attached to users and roles, not groups
  • Permissions boundaries are commonly used for delegated IAM administration
  • You can require permissions boundaries using IAM policy conditions
  • Permissions boundaries do NOT affect resource-based policies or SCPs

When to use (Comprehensive):

  • ✅ Use when: You want to delegate IAM administration without risking privilege escalation
  • ✅ Use when: You need to ensure users/roles cannot exceed certain permissions
  • ✅ Use when: You want to allow creating users/roles with restricted maximum permissions
  • ✅ Use when: Compliance requires limiting maximum permissions for certain roles
  • ❌ Don't use when: You have centralized IAM administration (no delegation needed)
  • ❌ Don't use when: You want to grant permissions (use identity-based policies instead)

Service Control Policies (SCPs) - Organizational Guardrails

What it is: Service Control Policies (SCPs) are policies applied to AWS Organizations that set the maximum permissions for accounts in an organization. SCPs act as guardrails, preventing accounts from performing certain actions regardless of IAM policies.

Why it exists: In multi-account environments, you need to enforce organization-wide security policies. SCPs ensure that even account administrators cannot violate organizational policies like "no public S3 buckets" or "only use approved regions."

Real-world analogy: SCPs are like corporate policies that apply to all employees regardless of their job title. Even the CEO must follow corporate policies like "no smoking in the building" or "must use approved vendors."

How it works (Detailed step-by-step):

  1. SCP Creation: You create an SCP defining allowed or denied actions at the organizational level.
  2. SCP Attachment: You attach the SCP to the organization root, organizational units (OUs), or individual accounts.
  3. Policy Inheritance: SCPs are inherited down the organizational hierarchy (root → OU → account).
  4. Policy Evaluation: When a principal in an account attempts an action, AWS evaluates SCPs, IAM policies, and resource-based policies.
  5. Effective Permissions: The effective permissions are the intersection of SCPs and IAM policies.
  6. Guardrail Enforcement: Even if an IAM policy allows an action, the SCP can deny it.

📊 SCP Evaluation Flow Diagram:

graph TB
    Root[Organization Root<br/>SCP: Allow all except<br/>organizations:LeaveOrganization]
    
    OU1[OU: Production<br/>SCP: Deny s3:PutBucketPublicAccessBlock<br/>if disabling public access]
    OU2[OU: Development<br/>SCP: Allow all]
    
    Account1[Account: Prod-App<br/>IAM Policy: Allow s3:*]
    Account2[Account: Dev-App<br/>IAM Policy: Allow s3:*]
    
    Action1[Action: s3:CreateBucket<br/>with public access]
    Action2[Action: s3:CreateBucket<br/>with public access]
    
    Root --> OU1
    Root --> OU2
    OU1 --> Account1
    OU2 --> Account2
    
    Account1 -->|❌ Denied by SCP| Action1
    Account2 -->|✅ Allowed| Action2
    
    style Action1 fill:#ffebee
    style Action2 fill:#c8e6c9
    style OU1 fill:#fff3e0

See: diagrams/05_domain4_service_control_policy_examples.mmd

Diagram Explanation (Detailed):

The diagram shows SCP evaluation in an AWS Organization. The organization root has an SCP that allows all actions except organizations:LeaveOrganization (prevents accounts from leaving the organization). The Production OU has an additional SCP that denies disabling S3 public access blocks (enforces that all S3 buckets must block public access). The Development OU has no additional restrictions. Account Prod-App in the Production OU has an IAM policy allowing s3:*. When a user attempts to create an S3 bucket with public access, the action is denied because the Production OU's SCP blocks it, even though the IAM policy allows it. Account Dev-App in the Development OU has the same IAM policy. When a user attempts to create an S3 bucket with public access, the action is allowed because the Development OU has no SCP restrictions. SCPs provide organizational guardrails that apply regardless of IAM policies, enabling centralized security enforcement across accounts.

Detailed Example 1: Preventing Public S3 Buckets Organization-Wide

A company wants to ensure no S3 buckets are ever made public. Here's how they use SCPs: (1) They create an SCP that denies s3:PutBucketPublicAccessBlock if the action would disable public access blocking. (2) They attach the SCP to the organization root, applying it to all accounts. (3) An account administrator attempts to disable public access blocking on a bucket. (4) The action is denied by the SCP, even though the administrator has full IAM permissions. (5) The administrator cannot create public buckets. (6) The company achieves organization-wide enforcement of the "no public buckets" policy. SCPs provided a guardrail that cannot be bypassed by account administrators.

Detailed Example 2: Restricting Regions for Compliance

A company must comply with data residency requirements allowing only US regions. Here's how they use SCPs: (1) They create an SCP that denies all actions in non-US regions:

{
  "Version": "2012-10-17",
  "Statement": [{
    "Effect": "Deny",
    "Action": "*",
    "Resource": "*",
    "Condition": {
      "StringNotEquals": {
        "aws:RequestedRegion": ["us-east-1", "us-west-2"]
      }
    }
  }]
}

(2) They attach the SCP to the organization root. (3) An account administrator attempts to launch an EC2 instance in eu-west-1. (4) The action is denied by the SCP. (5) The administrator can only launch resources in us-east-1 and us-west-2. (6) The company achieves compliance with data residency requirements. SCPs enforced regional restrictions across all accounts.

Must Know (Critical Facts):

  • SCPs do NOT grant permissions - they only filter/restrict permissions
  • SCPs apply to all principals in an account, including the root user (except management account)
  • The management account is NOT affected by SCPs
  • SCPs are inherited down the organizational hierarchy
  • Effective permissions = intersection of SCPs AND IAM policies
  • SCPs can use allow lists (default deny, explicitly allow) or deny lists (default allow, explicitly deny)
  • SCPs do NOT affect service-linked roles

Section 4: Troubleshooting IAM - Policy Simulator, Access Analyzer, and CloudTrail

Introduction

The problem: IAM policies are complex, and troubleshooting access issues can be challenging. Users report "Access Denied" errors, but determining the root cause requires understanding policy evaluation logic, checking multiple policy types, and analyzing CloudTrail logs. Without proper troubleshooting tools and techniques, resolving IAM issues is time-consuming.

The solution: AWS provides tools specifically designed for IAM troubleshooting: IAM Policy Simulator tests policies before deployment, IAM Access Analyzer identifies unintended access, IAM Access Advisor shows which services were accessed, and CloudTrail logs all IAM API calls. Together, these tools enable efficient IAM troubleshooting.

Why it's tested: Troubleshooting IAM is a critical skill for the Security Specialty exam. The exam tests your ability to use IAM tools to diagnose access issues, identify security risks, and validate policy changes before deployment.

Core Concepts

IAM Policy Simulator - Testing Policies Before Deployment

What it is: IAM Policy Simulator is a tool that simulates IAM policy evaluation without making actual API calls. It shows whether a specific action would be allowed or denied based on the policies attached to a user, role, or group.

Why it exists: Deploying incorrect IAM policies can cause production outages or security vulnerabilities. Policy Simulator allows you to test policies in a safe environment before applying them, reducing the risk of errors.

Real-world analogy: Policy Simulator is like a flight simulator for pilots. Just as pilots practice maneuvers in a simulator before flying a real plane, you test IAM policies in the simulator before deploying them.

How it works (Detailed step-by-step):

  1. Select Principal: You select the IAM user, role, or group to simulate.
  2. Select Actions: You specify which actions to test (e.g., s3:GetObject, ec2:RunInstances).
  3. Specify Resources: You specify the resources the actions would be performed on (e.g., arn:aws:s3:::my-bucket/*).
  4. Policy Evaluation: Policy Simulator evaluates all policies attached to the principal: identity-based policies, permissions boundaries, resource-based policies, and SCPs.
  5. Result Display: Policy Simulator shows whether each action would be allowed or denied, and which policies contributed to the decision.
  6. Detailed Explanation: For denied actions, Policy Simulator explains why (e.g., "Denied by permissions boundary").

Detailed Example 1: Testing a New Policy Before Deployment

A security engineer creates a new IAM policy for developers. Here's how they use Policy Simulator: (1) They create a policy granting s3:GetObject and s3:PutObject on arn:aws:s3:::dev-bucket/*. (2) Before attaching the policy, they open Policy Simulator. (3) They select a test user and simulate s3:GetObject on arn:aws:s3:::dev-bucket/file.txt. (4) Policy Simulator shows "Allowed" with the new policy as the reason. (5) They simulate s3:DeleteObject on the same resource. (6) Policy Simulator shows "Denied" because the policy doesn't grant delete permissions. (7) They simulate s3:GetObject on arn:aws:s3:::prod-bucket/file.txt. (8) Policy Simulator shows "Denied" because the policy only allows access to dev-bucket. (9) The engineer confirms the policy works as intended. (10) They deploy the policy with confidence. Policy Simulator prevented potential access issues by testing before deployment.

Detailed Example 2: Troubleshooting Access Denied Errors

A developer reports they cannot access an S3 bucket despite having the correct policy. Here's how Policy Simulator helps: (1) The security team opens Policy Simulator and selects the developer's IAM user. (2) They simulate s3:GetObject on the bucket the developer is trying to access. (3) Policy Simulator shows "Denied" and lists the reason: "Denied by permissions boundary". (4) The team realizes the developer has a permissions boundary that doesn't include S3 actions. (5) They update the permissions boundary to include S3 actions. (6) They re-run the simulation and it shows "Allowed". (7) The developer can now access the bucket. Policy Simulator quickly identified the root cause of the access denial.

Detailed Example 3: Validating Cross-Account Access

A company wants to grant a partner account access to an S3 bucket. Here's how they use Policy Simulator: (1) They create a bucket policy allowing s3:GetObject from the partner account. (2) They create an IAM role in the partner account with a policy allowing s3:GetObject on the bucket. (3) They use Policy Simulator to test the partner role. (4) They simulate s3:GetObject on the bucket. (5) Policy Simulator shows "Allowed" and lists both the bucket policy and the role policy as reasons. (6) They simulate s3:PutObject on the bucket. (7) Policy Simulator shows "Denied" because neither policy grants put permissions. (8) They confirm cross-account access works as intended. Policy Simulator validated the cross-account configuration before granting access.

Must Know (Critical Facts):

  • Policy Simulator evaluates all policy types: identity-based, resource-based, permissions boundaries, and SCPs
  • Policy Simulator does NOT make actual API calls - it only simulates policy evaluation
  • Policy Simulator can test policies before they're attached to principals
  • Policy Simulator shows which policies contributed to allow or deny decisions
  • Policy Simulator is available in the AWS Console and via API (iam:SimulatePrincipalPolicy)
  • Policy Simulator does NOT simulate session policies or temporary credentials from STS

When to use (Comprehensive):

  • ✅ Use when: Testing new IAM policies before deployment
  • ✅ Use when: Troubleshooting "Access Denied" errors
  • ✅ Use when: Validating cross-account access configurations
  • ✅ Use when: Verifying permissions boundaries work as intended
  • ✅ Use when: Confirming least privilege policies grant only necessary permissions
  • ❌ Don't use when: You need to test actual API calls (use a test environment instead)
  • ❌ Don't use when: You need to simulate session policies (Policy Simulator doesn't support them)

IAM Access Analyzer - Identifying Unintended Access

What it is: IAM Access Analyzer continuously monitors your AWS resources and identifies resources that are shared with external entities. It uses automated reasoning to analyze resource policies and determine what access is granted to principals outside your AWS account or organization.

Why it exists: Resource-based policies can inadvertently grant access to external entities, creating security risks. Manually reviewing all resource policies is impractical. Access Analyzer automates this process, identifying unintended external access.

Real-world analogy: IAM Access Analyzer is like a security audit that continuously checks all doors and windows in your building to ensure only authorized people can enter. If a door is accidentally left unlocked, the audit immediately alerts you.

How it works (Detailed step-by-step):

  1. Analyzer Creation: You create an Access Analyzer for your account or organization.
  2. Resource Discovery: Access Analyzer discovers all resources with resource-based policies (S3 buckets, IAM roles, KMS keys, Lambda functions, etc.).
  3. Policy Analysis: Access Analyzer uses automated reasoning to analyze resource policies and determine what access is granted.
  4. External Access Detection: Access Analyzer identifies resources that grant access to principals outside your zone of trust (account or organization).
  5. Finding Generation: For each resource with external access, Access Analyzer generates a finding with details: resource ARN, external principal, actions granted, and conditions.
  6. Continuous Monitoring: Access Analyzer continuously monitors for policy changes and generates new findings when external access is detected.
  7. Integration: Findings are sent to Security Hub for centralized management.

📊 IAM Access Analyzer Diagram:

graph TB
    subgraph "Your AWS Account"
        S3[S3 Bucket<br/>Bucket Policy]
        IAM[IAM Role<br/>Trust Policy]
        KMS[KMS Key<br/>Key Policy]
        Lambda[Lambda Function<br/>Resource Policy]
    end
    
    subgraph "IAM Access Analyzer"
        Analyzer[Access Analyzer<br/>Zone of Trust: Account]
        Analysis[Automated Reasoning<br/>Policy Analysis]
        Findings[Findings<br/>External Access Detected]
    end
    
    External1[External Account<br/>111122223333]
    External2[Public Access<br/>*]
    
    S3 -.->|Policy Analysis| Analyzer
    IAM -.->|Policy Analysis| Analyzer
    KMS -.->|Policy Analysis| Analyzer
    Lambda -.->|Policy Analysis| Analyzer
    
    Analyzer --> Analysis
    Analysis --> Findings
    
    Findings -.->|Finding: S3 bucket<br/>allows External Account| External1
    Findings -.->|Finding: Lambda<br/>allows Public Access| External2
    
    SecurityHub[Security Hub<br/>Centralized Findings]
    Findings --> SecurityHub
    
    style Findings fill:#ffebee
    style Analyzer fill:#c8e6c9

See: diagrams/05_domain4_iam_access_analyzer.mmd

Diagram Explanation (Detailed):

The diagram shows IAM Access Analyzer monitoring resources in an AWS account. Access Analyzer is configured with a zone of trust set to the account (meaning any access from outside the account is considered external). Access Analyzer continuously discovers resources with resource-based policies: S3 buckets with bucket policies, IAM roles with trust policies, KMS keys with key policies, and Lambda functions with resource policies. For each resource, Access Analyzer uses automated reasoning to analyze the policy and determine what access is granted. Access Analyzer identifies two findings: (1) An S3 bucket grants access to an external account (111122223333), and (2) A Lambda function allows public access (principal: *). These findings are generated with details about the resource, the external principal, and the actions granted. Findings are sent to Security Hub for centralized security management. Access Analyzer provides continuous monitoring, automatically detecting new external access as policies change.

Detailed Example 1: Detecting Unintended S3 Bucket Sharing

A company wants to ensure no S3 buckets are shared externally. Here's how Access Analyzer helps: (1) They enable Access Analyzer with the zone of trust set to their organization. (2) Access Analyzer scans all S3 buckets and analyzes bucket policies. (3) Access Analyzer generates a finding: "S3 bucket 'customer-data' grants s3:GetObject to account 111122223333". (4) The security team investigates and discovers the bucket policy was added by mistake during testing. (5) They remove the external access from the bucket policy. (6) Access Analyzer rescans and the finding is resolved. (7) The team sets up an EventBridge rule to alert on new Access Analyzer findings. (8) A week later, a developer accidentally adds a bucket policy granting public read access. (9) Access Analyzer immediately generates a finding and triggers an alert. (10) The security team removes the public access within minutes. Access Analyzer continuously monitored for unintended external access, preventing data exposure.

Detailed Example 2: Validating Cross-Account IAM Role Trust Policies

A company uses cross-account IAM roles for partner access. Here's how Access Analyzer helps: (1) They enable Access Analyzer and review findings. (2) Access Analyzer shows 5 IAM roles with trust policies allowing external accounts. (3) The security team reviews each finding to validate the external access is intentional. (4) They find 4 roles are correctly configured for approved partners. (5) They find 1 role trusts an unknown external account. (6) They investigate and discover the role was created for a former partner and should have been deleted. (7) They delete the role, removing the unintended external access. (8) Access Analyzer helped identify a forgotten role that posed a security risk. Access Analyzer provided visibility into all external access, enabling security validation.

Detailed Example 3: Monitoring KMS Key Policies for External Access

A company wants to ensure KMS keys are not shared externally. Here's how Access Analyzer helps: (1) They enable Access Analyzer and filter findings to show only KMS keys. (2) Access Analyzer shows 2 KMS keys with external access. (3) The security team reviews the first key and finds it's shared with an approved partner for encrypted data exchange. (4) They mark the finding as "Archived" to indicate it's intentional. (5) They review the second key and find it grants kms:Decrypt to a public principal (*). (6) They investigate and discover the key policy was misconfigured. (7) They update the key policy to remove public access. (8) Access Analyzer rescans and the finding is resolved. Access Analyzer identified a critical misconfiguration that could have allowed anyone to decrypt sensitive data.

Must Know (Critical Facts):

  • Access Analyzer uses automated reasoning (mathematical logic) to analyze policies
  • Access Analyzer identifies external access based on the zone of trust (account or organization)
  • Access Analyzer supports multiple resource types: S3, IAM roles, KMS keys, Lambda, SQS, SNS, Secrets Manager, and more
  • Access Analyzer findings include: resource ARN, external principal, actions granted, and conditions
  • Access Analyzer integrates with Security Hub for centralized findings management
  • Access Analyzer can generate findings for public access (principal: *) and cross-account access
  • Access Analyzer findings can be archived if the external access is intentional

When to use (Comprehensive):

  • ✅ Use when: You need to identify resources shared with external entities
  • ✅ Use when: You want continuous monitoring for unintended external access
  • ✅ Use when: Compliance requires auditing external access to resources
  • ✅ Use when: You want to validate cross-account access configurations
  • ✅ Use when: You need to detect public access to resources
  • ❌ Don't use when: You only have identity-based policies (Access Analyzer focuses on resource-based policies)
  • ❌ Don't use when: You don't have resources with resource-based policies

IAM Access Advisor - Understanding Service Usage

What it is: IAM Access Advisor shows which AWS services an IAM user, role, or group has accessed and when they last accessed them. It helps identify unused permissions that can be removed to implement least privilege.

Why it exists: IAM policies often grant more permissions than needed. Without visibility into actual service usage, it's difficult to identify and remove unused permissions. Access Advisor provides this visibility, enabling least privilege implementation.

Real-world analogy: IAM Access Advisor is like a building access log that shows which rooms each employee entered and when. If an employee has a key to a room they never visit, you can revoke that key.

How it works (Detailed step-by-step):

  1. Data Collection: AWS tracks which services each IAM principal accesses and when.
  2. Access Advisor View: You open Access Advisor for a specific IAM user, role, or group.
  3. Service List: Access Advisor displays all AWS services the principal has permissions for.
  4. Last Accessed: For each service, Access Advisor shows when it was last accessed (or "Never accessed").
  5. Permission Reduction: You identify services that were never accessed or not accessed recently.
  6. Policy Update: You remove permissions for unused services to implement least privilege.

Detailed Example 1: Implementing Least Privilege with Access Advisor

A company wants to reduce permissions for a developer role. Here's how they use Access Advisor: (1) The developer role has a policy granting permissions for 20 AWS services. (2) The security team opens Access Advisor for the role. (3) Access Advisor shows the role accessed 8 services in the last 90 days. (4) Access Advisor shows 12 services were never accessed. (5) The team creates a new policy granting permissions only for the 8 accessed services. (6) They test the new policy in a non-production environment. (7) They replace the old policy with the new, more restrictive policy. (8) The role now follows the principle of least privilege. (9) The team schedules quarterly reviews using Access Advisor to continuously refine permissions. Access Advisor enabled data-driven least privilege implementation.

Detailed Example 2: Identifying Unused IAM Roles

A company wants to identify and delete unused IAM roles. Here's how they use Access Advisor: (1) They list all IAM roles in their account (200 roles). (2) They use Access Advisor to check when each role was last used. (3) They find 50 roles that haven't been used in over 180 days. (4) They investigate these roles and find 30 were created for temporary projects that are now complete. (5) They delete the 30 unused roles. (6) They find 20 roles are for disaster recovery and should be retained. (7) They tag these roles as "DR" for future reference. Access Advisor helped identify and remove unused roles, reducing attack surface.

Must Know (Critical Facts):

  • Access Advisor shows service-level access, not action-level access
  • Access Advisor data is updated daily (not real-time)
  • Access Advisor tracks access for the last 400 days
  • Access Advisor shows "Never accessed" for services that were never used
  • Access Advisor is available for IAM users, roles, and groups
  • Access Advisor helps implement least privilege by identifying unused permissions

When to use (Comprehensive):

  • ✅ Use when: Implementing least privilege by removing unused permissions
  • ✅ Use when: Identifying unused IAM roles for deletion
  • ✅ Use when: Auditing which services are actually being used
  • ✅ Use when: Validating that permissions are being used as intended
  • ❌ Don't use when: You need real-time access data (Access Advisor updates daily)
  • ❌ Don't use when: You need action-level details (use CloudTrail instead)

CloudTrail - Auditing IAM API Calls

What it is: AWS CloudTrail logs all API calls made in your AWS account, including IAM API calls. CloudTrail provides a complete audit trail of who did what, when, and from where.

Why it exists: For security and compliance, you need to audit all actions in your AWS account. CloudTrail provides this audit trail, enabling forensic analysis, compliance reporting, and security monitoring.

Real-world analogy: CloudTrail is like a security camera system that records everything happening in your building. If something goes wrong, you can review the footage to see what happened.

How it works (Detailed step-by-step):

  1. Trail Creation: You create a CloudTrail trail to log API calls.
  2. Event Capture: CloudTrail captures all API calls made in your account.
  3. Event Logging: CloudTrail logs events to S3 and optionally to CloudWatch Logs.
  4. Event Details: Each log entry includes: who made the call, what action was performed, when it occurred, source IP, and response.
  5. Analysis: You can query CloudTrail logs using Athena or CloudWatch Logs Insights.

Detailed Example 1: Investigating an Access Denied Error

A user reports an "Access Denied" error. Here's how CloudTrail helps: (1) The security team searches CloudTrail logs for the user's API calls. (2) They find the failed API call: s3:GetObject on arn:aws:s3:::prod-bucket/file.txt. (3) The CloudTrail log shows errorCode: AccessDenied and errorMessage: User is not authorized. (4) They use Policy Simulator to test the user's permissions. (5) Policy Simulator shows the user's policy allows s3:GetObject on dev-bucket/* but not prod-bucket/*. (6) They realize the user is trying to access the wrong bucket. (7) They inform the user to use the dev-bucket instead. CloudTrail provided the audit trail needed to diagnose the issue.

Must Know (Critical Facts):

  • CloudTrail logs all API calls, including IAM actions
  • CloudTrail logs include: principal, action, resource, timestamp, source IP, and response
  • CloudTrail logs can be analyzed using Athena or CloudWatch Logs Insights
  • CloudTrail is essential for security auditing and compliance
  • CloudTrail logs should be encrypted and stored in a secure S3 bucket

Chapter Summary

What We Covered

This chapter covered Domain 4: Identity and Access Management (16% of exam), including:

  • Authentication: IAM users, federation, IAM Identity Center, Cognito, MFA
  • Authorization: IAM policies, RBAC, ABAC, least privilege, SCPs
  • Temporary Credentials: STS, AssumeRole, session tokens, external ID
  • Policy Types: Identity-based, resource-based, session policies, permissions boundaries
  • Troubleshooting: CloudTrail, IAM Access Advisor, Policy Simulator, Access Analyzer

Critical Takeaways

  1. IAM Policies: Identity-based (attached to users/roles), resource-based (attached to resources)
  2. Policy Evaluation: Explicit deny > explicit allow > implicit deny
  3. RBAC: Role-based access control, assign permissions to roles
  4. ABAC: Attribute-based access control, use tags for dynamic permissions
  5. STS: Temporary credentials, AssumeRole for cross-account access
  6. MFA: Multi-factor authentication, enforce with IAM policies
  7. Federation: SAML, OIDC, integrate with external identity providers
  8. Least Privilege: Grant minimum permissions needed, use Access Analyzer
  9. SCPs: Service Control Policies, organization-wide guardrails
  10. Troubleshooting: CloudTrail for API calls, Policy Simulator for testing

Self-Assessment Checklist

Test yourself before moving on:

  • I understand the difference between authentication and authorization
  • I can write IAM policies with proper syntax
  • I know the policy evaluation logic (deny > allow > deny)
  • I understand RBAC vs ABAC and when to use each
  • I can design a federation strategy (SAML, OIDC)
  • I know how to use STS for temporary credentials
  • I understand cross-account access patterns
  • I can troubleshoot access denied errors
  • I know how to implement least privilege
  • I understand SCPs and permissions boundaries

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-25 (Authentication focus)
  • Domain 4 Bundle 2: Questions 26-50 (Authorization focus)
  • Identity & Access Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: Policy evaluation logic, ABAC implementation, STS usage
  • Focus on: Policy syntax, troubleshooting, federation patterns

Quick Reference Card

Key Concepts:

  • IAM User: Long-term credentials, for humans or applications
  • IAM Role: Temporary credentials, assumed by users or services
  • IAM Policy: JSON document defining permissions
  • STS: Security Token Service, issues temporary credentials
  • Federation: External identity provider integration
  • MFA: Multi-factor authentication, adds security layer

Policy Types:

  • Identity-based: Attached to users, groups, roles
  • Resource-based: Attached to resources (S3, KMS, etc.)
  • Session policies: Limit permissions during AssumeRole
  • Permissions boundaries: Maximum permissions for users/roles
  • SCPs: Organization-wide permission limits

Decision Points:

  • Need long-term credentials? → IAM User (avoid if possible)
  • Need temporary credentials? → IAM Role + STS
  • Need cross-account access? → AssumeRole with external ID
  • Need external identity provider? → Federation (SAML/OIDC)
  • Need to limit permissions? → Permissions boundaries or SCPs
  • Need dynamic permissions? → ABAC with tags
  • Need to troubleshoot access? → CloudTrail + Policy Simulator

Best Practices:

  1. Use IAM roles instead of users when possible
  2. Enable MFA for all users
  3. Implement least privilege
  4. Use ABAC for scalable permissions
  5. Rotate credentials regularly
  6. Use temporary credentials (STS)
  7. Enable CloudTrail for auditing
  8. Use Access Analyzer to identify overly permissive access
  9. Implement SCPs for organization-wide guardrails
  10. Test policies with Policy Simulator

Chapter 4 Complete

Next Chapter: 06_domain5_data_protection - Data Protection (18% of exam)


Chapter Summary

What We Covered

This chapter explored Identity and Access Management, the foundation of AWS security:

Authentication: Creating and managing identities with federation, identity providers, IAM Identity Center, and Cognito; understanding long-term and temporary credentials; troubleshooting authentication with CloudTrail, IAM Access Advisor, and IAM policy simulator; and implementing multi-factor authentication (MFA).

Authorization: Understanding IAM policy types (managed, inline, identity-based, resource-based, session control policies); mastering policy components (Principal, Action, Resource, Condition); constructing ABAC and RBAC strategies; applying the principle of least privilege; and troubleshooting authorization issues.

Critical Takeaways

  1. Authentication vs Authorization: Authentication proves who you are (identity), authorization determines what you can do (permissions). Both are required for secure access.

  2. Temporary Credentials are Preferred: Use STS temporary credentials (AssumeRole) instead of long-term access keys whenever possible. Temporary credentials automatically expire and reduce the risk of credential compromise.

  3. Federation for Scale: Use federation (SAML, OIDC) to integrate with existing identity providers (Active Directory, Okta, etc.) rather than creating IAM users for every person. IAM Identity Center simplifies multi-account federation.

  4. MFA is Non-Negotiable: Enable MFA for all human users, especially those with privileged access. Use MFA conditions in IAM policies to enforce MFA for sensitive operations.

  5. Policy Evaluation is Complex: Understand the policy evaluation logic: explicit deny always wins, then explicit allow, then implicit deny. SCPs, permissions boundaries, session policies, and resource policies all affect the final decision.

  6. Least Privilege is a Journey: Start with broad permissions, use IAM Access Advisor to identify unused permissions, then progressively reduce permissions to the minimum required. Automate this with IAM Access Analyzer.

  7. ABAC Scales Better: Attribute-Based Access Control (ABAC) using tags scales better than Role-Based Access Control (RBAC) for large environments. Instead of creating a role per project, use tags to control access.

  8. Separation of Duties: Use permissions boundaries to delegate permission management while preventing privilege escalation. Administrators can create roles but can't grant more permissions than their boundary allows.

Self-Assessment Checklist

Test yourself before moving on:

  • I understand the difference between authentication and authorization
  • I can design federation solutions using SAML and OIDC
  • I know how to configure IAM Identity Center for multi-account access
  • I understand Cognito User Pools and Identity Pools
  • I can explain when to use long-term credentials vs temporary credentials
  • I know how to use STS AssumeRole for cross-account access
  • I can troubleshoot authentication failures using CloudTrail
  • I understand how to use IAM Access Advisor and IAM policy simulator
  • I can implement MFA for IAM users and enforce MFA with policies
  • I know the difference between managed policies and inline policies
  • I understand identity-based policies vs resource-based policies
  • I can explain session policies and permissions boundaries
  • I know how SCPs work in AWS Organizations
  • I understand policy evaluation logic (explicit deny, explicit allow, implicit deny)
  • I can write IAM policies with Principal, Action, Resource, and Condition elements
  • I know how to use condition operators (StringEquals, IpAddress, DateGreaterThan, etc.)
  • I can implement ABAC using tags
  • I understand the difference between RBAC and ABAC
  • I can apply the principle of least privilege using IAM Access Analyzer
  • I know how to implement separation of duties with permissions boundaries
  • I can troubleshoot authorization errors using CloudTrail and policy simulator
  • I understand how to detect and prevent privilege escalation

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-25 (Authentication and Federation)
  • Domain 4 Bundle 2: Questions 26-50 (Authorization and Policies)
  • Identity & Access Bundle: All 50 questions (IAM-specific scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review policy evaluation logic and the order of precedence
  • Practice writing IAM policies with conditions
  • Study the differences between ABAC and RBAC
  • Focus on federation scenarios (SAML, OIDC, IAM Identity Center)
  • Review STS AssumeRole and cross-account access patterns

Quick Reference Card

Authentication Services:

  • IAM Users: Long-term credentials (access keys, passwords)
  • IAM Roles: Temporary credentials via STS AssumeRole
  • IAM Identity Center: Centralized SSO for multi-account access
  • Cognito User Pools: User directory for applications
  • Cognito Identity Pools: Temporary AWS credentials for app users
  • STS: Security Token Service for temporary credentials
  • Federation: SAML 2.0 and OIDC integration with external identity providers

Authorization Services:

  • IAM Policies: JSON documents defining permissions
  • SCPs: Service Control Policies in AWS Organizations (guardrails)
  • Permissions Boundaries: Maximum permissions for IAM entities
  • Session Policies: Temporary permission restrictions for assumed roles
  • Resource Policies: Policies attached to resources (S3, KMS, etc.)

Policy Types:

  • Managed Policies: Standalone policies (AWS managed or customer managed)
  • Inline Policies: Embedded directly in IAM user, group, or role
  • Identity-Based: Attached to IAM identities (users, groups, roles)
  • Resource-Based: Attached to resources (S3 buckets, KMS keys, etc.)
  • Session Policies: Passed when assuming a role (further restricts permissions)
  • Permissions Boundaries: Maximum permissions (doesn't grant, only limits)

Policy Components:

  • Principal: Who can access (user, role, account, service)
  • Action: What operations are allowed (s3:GetObject, ec2:DescribeInstances)
  • Resource: Which resources (ARNs)
  • Condition: When access is allowed (IP address, MFA, time, tags)
  • Effect: Allow or Deny

Policy Evaluation Logic:

  1. Explicit Deny: If any policy has an explicit deny, access is denied (highest priority)
  2. SCPs: Organization SCPs must allow the action
  3. Permissions Boundaries: Boundary must allow the action
  4. Session Policies: Session policy must allow the action (if present)
  5. Identity-Based or Resource-Based: At least one must explicitly allow
  6. Implicit Deny: If no explicit allow, access is denied (default)

Decision Points:

  • Human users → IAM Identity Center with federation (SAML/OIDC)
  • Application users → Cognito User Pools + Identity Pools
  • Cross-account access → IAM roles with AssumeRole
  • Service-to-service → IAM service roles
  • EC2 instances → IAM instance roles (never access keys)
  • Temporary access → STS temporary credentials
  • Large-scale permissions → ABAC with tags
  • Delegation with limits → Permissions boundaries
  • Organization-wide guardrails → SCPs

Exam Tips:

  • Know the policy evaluation order: explicit deny → SCPs → boundaries → session policies → identity/resource policies → implicit deny
  • Understand that SCPs don't grant permissions, they only limit what can be granted
  • Remember that permissions boundaries don't grant permissions, they only set maximum permissions
  • IAM Identity Center is the preferred solution for multi-account SSO (replaces SAML federation)
  • Cognito User Pools are for authentication, Identity Pools are for authorization (AWS credentials)
  • Always use temporary credentials (STS) instead of long-term access keys when possible
  • ABAC scales better than RBAC for large environments with many resources
  • MFA conditions in policies enforce MFA for sensitive operations


Chapter Summary

What We Covered

This chapter explored AWS Identity and Access Management across two critical areas:

Authentication for AWS Resources

  • Creating and managing identities (federation, identity providers, IAM Identity Center, Cognito)
  • Understanding long-term credentials (IAM users, access keys) vs temporary credentials (STS)
  • Troubleshooting authentication issues using CloudTrail, IAM Access Advisor, and IAM policy simulator
  • Implementing multi-factor authentication (MFA) for enhanced security

Authorization for AWS Resources

  • Understanding IAM policy types (managed, inline, identity-based, resource-based, session control)
  • Policy components and their impact (Principal, Action, Resource, Condition)
  • Designing ABAC (Attribute-Based Access Control) and RBAC (Role-Based Access Control) strategies
  • Applying the principle of least privilege across environments
  • Troubleshooting authorization issues and investigating unintended permissions

Critical Takeaways

  1. Prefer temporary credentials: Use IAM roles with STS temporary credentials instead of long-term access keys whenever possible
  2. Federation for human users: Use IAM Identity Center (SSO) or SAML federation instead of creating IAM users for employees
  3. Cognito for application users: Use Cognito User Pools for authentication and Identity Pools for temporary AWS credentials
  4. MFA is mandatory: Enforce MFA for all human users, especially for privileged operations and root account access
  5. Policy evaluation logic: Explicit deny always wins, then explicit allow, default deny for everything else
  6. Least privilege principle: Grant only the minimum permissions needed to perform a task, nothing more
  7. ABAC scales better: Use attribute-based access control (tags) for dynamic, scalable permission management
  8. Permissions boundaries: Use permissions boundaries to set maximum permissions for IAM entities
  9. SCPs control accounts: Service Control Policies in Organizations set guardrails for entire accounts
  10. IAM Access Analyzer: Use Access Analyzer to identify resources shared with external entities and unused permissions
  11. Session policies: Use session policies to further restrict temporary credentials from AssumeRole
  12. Condition keys: Use condition keys (IP address, MFA, time, tags) to add context-based restrictions

Self-Assessment Checklist

Test yourself before moving on:

Authentication:

  • I can design authentication solutions using federation, IAM Identity Center, and Cognito
  • I understand the differences between SAML, OIDC, and web identity federation
  • I know when to use IAM users vs federated identities vs Cognito
  • I can troubleshoot authentication failures using CloudTrail and IAM tools
  • I understand how to implement and enforce MFA for different scenarios
  • I know how STS temporary credentials work and when to use them

Authorization:

  • I can write IAM policies using all policy types (managed, inline, identity-based, resource-based)
  • I understand policy evaluation logic and how different policy types interact
  • I can design ABAC strategies using tags for scalable access control
  • I know how to implement RBAC using IAM roles and groups
  • I can use condition keys to add context-based restrictions to policies
  • I understand permissions boundaries and how they limit permissions
  • I can troubleshoot authorization issues using IAM policy simulator and Access Analyzer
  • I know how to apply the principle of least privilege systematically

Advanced Concepts:

  • I can design cross-account access using IAM roles and resource policies
  • I understand how SCPs in Organizations control account permissions
  • I can use session policies to restrict temporary credentials
  • I know how to use IAM Access Analyzer to identify security risks
  • I can investigate unintended permissions and privilege escalation paths

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-25 (Authentication)
  • Domain 4 Bundle 2: Questions 26-50 (Authorization)
  • Identity & Access Bundle: Questions 1-50 (IAM-specific scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review policy evaluation logic and how different policy types interact
  • Practice writing IAM policies with various condition keys
  • Focus on understanding federation flows (SAML, OIDC, Cognito)
  • Review ABAC implementation using tags and session tags

Quick Reference Card

Key Services:

  • IAM: Identity and Access Management for AWS resources
  • IAM Identity Center (SSO): Centralized access management for multiple AWS accounts
  • Cognito: User authentication and authorization for web/mobile applications
  • STS: Security Token Service for temporary credentials
  • IAM Access Analyzer: Identifies resources shared externally and unused permissions
  • Organizations: Multi-account management with Service Control Policies

Key Concepts:

  • Authentication: Verifying identity (who you are)
  • Authorization: Determining permissions (what you can do)
  • Federation: Using external identity providers (SAML, OIDC)
  • Temporary Credentials: Short-lived credentials from STS (more secure than access keys)
  • RBAC: Role-Based Access Control (permissions based on job function)
  • ABAC: Attribute-Based Access Control (permissions based on tags/attributes)
  • Least Privilege: Minimum permissions needed to perform a task
  • Permissions Boundary: Maximum permissions an IAM entity can have
  • SCP: Service Control Policy (guardrails for AWS accounts in Organizations)

Policy Types:

  • Identity-based: Attached to IAM users, groups, or roles
  • Resource-based: Attached to resources (S3 buckets, KMS keys, Lambda functions)
  • Permissions boundaries: Set maximum permissions for IAM entities
  • Session policies: Restrict temporary credentials from AssumeRole
  • SCPs: Control permissions for entire AWS accounts in Organizations

Decision Points:

  • Human users → IAM Identity Center (SSO) or SAML federation (not IAM users)
  • Application users → Cognito User Pools (authentication) + Identity Pools (AWS access)
  • Service-to-service → IAM roles (EC2 instance roles, Lambda execution roles)
  • Cross-account access → IAM roles with trust policies
  • Temporary credentials → STS AssumeRole (always prefer over access keys)
  • MFA enforcement → IAM policy with MFA condition key
  • Scalable permissions → ABAC using tags (not RBAC with many roles)
  • Maximum permissions → Permissions boundaries
  • Account guardrails → Service Control Policies (SCPs)
  • External access detection → IAM Access Analyzer
  • Unused permissions → IAM Access Advisor

Policy Evaluation Logic:

  1. Explicit Deny (always wins)
  2. Explicit Allow (from any policy)
  3. Implicit Deny (default)

Condition Keys (Common):

  • aws:SourceIp: Restrict by IP address
  • aws:MultiFactorAuthPresent: Require MFA
  • aws:CurrentTime: Time-based restrictions
  • aws:PrincipalTag/*: Tag-based restrictions (ABAC)
  • aws:RequestedRegion: Region restrictions

  1. Default Deny (if no explicit allow)

Common Mistakes:

  • Forgetting that explicit deny always wins (even over explicit allow)
  • Not understanding that permissions boundaries limit maximum permissions
  • Confusing identity-based policies with resource-based policies
  • Assuming that removing a policy immediately revokes access (cached credentials)

Chapter Summary

What We Covered

This chapter covered Identity and Access Management, accounting for 16% of the SCS-C02 exam. We explored two major task areas:

Task 4.1: Authentication for AWS Resources

  • Creating and managing identities using federation, identity providers, IAM Identity Center, and Cognito
  • Understanding long-term credentials (IAM access keys) vs. temporary credentials (STS)
  • Troubleshooting authentication issues using CloudTrail, IAM Access Advisor, and IAM policy simulator
  • Implementing multi-factor authentication (MFA) for users and API calls

Task 4.2: Authorization for AWS Resources

  • Understanding IAM policy types (managed, inline, identity-based, resource-based, session control, permissions boundaries, SCPs)
  • Constructing ABAC (Attribute-Based Access Control) and RBAC (Role-Based Access Control) strategies
  • Interpreting policy components (Principal, Action, Resource, Condition)
  • Applying the principle of least privilege and enforcing separation of duties
  • Troubleshooting authorization issues and investigating unintended permissions

Critical Takeaways

  1. Temporary Credentials are Always Better: Never use long-term IAM access keys when temporary credentials from STS AssumeRole are available. Temporary credentials automatically expire and reduce risk.

  2. IAM Identity Center for Human Users: For human users, use IAM Identity Center (AWS SSO) or SAML federation. Never create individual IAM users for employees.

  3. Cognito for Application Users: For mobile/web applications, use Cognito User Pools for authentication and Cognito Identity Pools for temporary AWS credentials.

  4. Explicit Deny Always Wins: In policy evaluation, an explicit deny in any policy (identity-based, resource-based, SCP, permissions boundary) always overrides any explicit allow.

  5. ABAC Scales Better Than RBAC: For large organizations, use Attribute-Based Access Control (ABAC) with tags instead of creating hundreds of roles. ABAC uses tags to control access dynamically.

  6. Permissions Boundaries Limit Maximum Permissions: Permissions boundaries set the maximum permissions an IAM entity can have, even if other policies grant more permissions.

  7. SCPs Control Entire Accounts: Service Control Policies (SCPs) in AWS Organizations control what actions are allowed in member accounts, regardless of IAM policies.

  8. MFA Should Be Enforced: Use IAM policies with MFA condition keys to require MFA for sensitive operations (deleting resources, accessing production, etc.).

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Authentication:

  • Explain the difference between IAM users, IAM Identity Center, and SAML federation
  • Configure Cognito User Pools for user authentication
  • Set up Cognito Identity Pools to provide temporary AWS credentials
  • Use STS AssumeRole to obtain temporary credentials
  • Troubleshoot authentication failures using CloudTrail logs
  • Implement MFA for IAM users and enforce MFA for API calls

Authorization:

  • Write identity-based policies with Principal, Action, Resource, and Condition
  • Explain the difference between identity-based and resource-based policies
  • Configure permissions boundaries to limit maximum permissions
  • Create Service Control Policies (SCPs) to restrict account-level actions
  • Design an ABAC strategy using tags for scalable access control
  • Use IAM Access Analyzer to identify external access to resources
  • Troubleshoot authorization errors using IAM policy simulator

Policy Evaluation:

  • Explain the policy evaluation logic (explicit deny → explicit allow → default deny)
  • Understand how SCPs, permissions boundaries, and session policies interact
  • Identify which policy type is causing an access denial
  • Use CloudTrail to investigate authorization failures

Decision-Making:

  • Choose between IAM users, IAM Identity Center, and federation for different scenarios
  • Determine when to use ABAC vs. RBAC
  • Select between Secrets Manager and Parameter Store for credential storage
  • Decide when to use permissions boundaries vs. SCPs

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-40 (focus on authentication and identity management)
  • Domain 4 Bundle 2: Questions 41-80 (focus on authorization and policy evaluation)
  • Identity & Access Bundle: Questions covering IAM, IAM Identity Center, Cognito, STS, Organizations
  • Full Practice Test 1: Domain 4 questions (8 questions, 16% of exam)

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • IAM Policy Evaluation Logic (if you struggled with policy precedence questions)
    • ABAC vs. RBAC (if you struggled with scalable access control questions)
    • Cognito Authentication Flow (if you struggled with mobile/web app questions)
    • STS AssumeRole (if you struggled with temporary credential questions)
  • Focus on:
    • Understanding the differences between policy types (identity-based, resource-based, SCPs, permissions boundaries)
    • Practicing IAM policy simulator to test policy effects
    • Memorizing the policy evaluation logic (explicit deny → explicit allow → default deny)
    • Understanding when to use ABAC with tags vs. RBAC with roles

Quick Reference Card

Key Services:

  • IAM: Identity and Access Management for AWS resources (users, roles, policies)
  • IAM Identity Center: Centralized SSO for multiple AWS accounts and applications
  • Cognito: User authentication and authorization for mobile/web applications
  • STS: Security Token Service for temporary credentials
  • Organizations: Multi-account management with Service Control Policies (SCPs)
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • Temporary Credentials: Short-lived credentials from STS (preferred over access keys)
  • Federation: Allowing external identities (SAML, OIDC) to access AWS resources
  • ABAC: Attribute-Based Access Control using tags for scalable permissions
  • RBAC: Role-Based Access Control using roles for specific job functions
  • Permissions Boundaries: Maximum permissions for IAM entities
  • SCPs: Service Control Policies controlling account-level permissions
  • MFA: Multi-Factor Authentication for enhanced security

Policy Types:

  • Identity-based: Attached to IAM users, groups, or roles
  • Resource-based: Attached to resources (S3 buckets, KMS keys, Lambda functions)
  • Permissions boundaries: Set maximum permissions for IAM entities
  • Session policies: Restrict temporary credentials from AssumeRole
  • SCPs: Control permissions for entire AWS accounts in Organizations

Decision Points:

  • Human users → IAM Identity Center (SSO) or SAML federation (not IAM users)
  • Application users → Cognito User Pools (authentication) + Identity Pools (AWS access)
  • Service-to-service → IAM roles (EC2 instance roles, Lambda execution roles)
  • Cross-account access → IAM roles with trust policies
  • Temporary credentials → STS AssumeRole (always prefer over access keys)
  • MFA enforcement → IAM policy with MFA condition key
  • Scalable permissions → ABAC using tags (not RBAC with many roles)
  • Maximum permissions → Permissions boundaries
  • Account guardrails → Service Control Policies (SCPs)
  • External access detection → IAM Access Analyzer
  • Unused permissions → IAM Access Advisor

Policy Evaluation Logic:

  1. Explicit Deny (always wins)
  2. Explicit Allow (from any policy)
  3. Default Deny (if no explicit allow)

Next Steps

Before moving to Domain 5:

  1. Review the Quick Reference Card and ensure you can recall all key services and policy types
  2. Practice writing IAM policies with conditions (IP address, MFA, tags)
  3. Experiment with IAM policy simulator to test policy effects
  4. Set up IAM Identity Center if you have access to AWS Organizations

Moving Forward:

  • Domain 5 (Data Protection) will cover how to protect data using encryption and access controls
  • Understanding IAM policies is essential for controlling access to encrypted data
  • KMS key policies (covered in Domain 5) are a type of resource-based policy

Chapter Summary

What We Covered

This chapter covered Domain 4: Identity and Access Management (16% of the exam), focusing on two critical task areas:

Task 4.1: Design, implement, and troubleshoot authentication

  • Creating and managing identities using federation, identity providers, IAM Identity Center, and Cognito
  • Understanding long-term credentials (access keys) vs. temporary credentials (STS)
  • Troubleshooting authentication issues using CloudTrail, IAM Access Advisor, and IAM policy simulator
  • Implementing multi-factor authentication (MFA) for users and API calls

Task 4.2: Design, implement, and troubleshoot authorization

  • Understanding IAM policy types (managed, inline, identity-based, resource-based, session control)
  • Constructing ABAC (Attribute-Based Access Control) and RBAC (Role-Based Access Control) strategies
  • Evaluating policy components (Principal, Action, Resource, Condition)
  • Applying the principle of least privilege across environments
  • Troubleshooting authorization issues using CloudTrail, IAM Access Advisor, and IAM policy simulator

Critical Takeaways

  1. Always prefer IAM roles over access keys: Roles provide temporary credentials that automatically rotate. Access keys are long-term and require manual rotation.

  2. Use IAM Identity Center for workforce identities: Centralized SSO for multiple AWS accounts. Integrates with external identity providers (Active Directory, Okta, etc.).

  3. Use Cognito for customer identities: User pools for authentication, identity pools for temporary AWS credentials.

  4. MFA is mandatory for privileged access: Enforce MFA for root account, IAM users with admin permissions, and sensitive API calls.

  5. Policy evaluation logic: Explicit Deny → Explicit Allow → Default Deny. An explicit deny always wins.

  6. ABAC scales better than RBAC: Use tags to define permissions instead of creating many roles. Enables self-service and reduces administrative overhead.

  7. Permissions boundaries limit maximum permissions: Use to delegate permission management while preventing privilege escalation.

  8. SCPs are account-level guardrails: Applied at the organization or OU level. Cannot grant permissions, only restrict them.

  9. IAM Access Analyzer detects external access: Identifies resources shared with external entities. Use to prevent unintended public access.

  10. Session policies limit temporary credentials: Applied when assuming a role or federating. Cannot grant more permissions than the identity-based policy.

Self-Assessment Checklist

Test yourself before moving to Domain 5. You should be able to:

Authentication:

  • Explain the difference between IAM users, IAM roles, and federated identities
  • Design a SAML 2.0 federation architecture with an external identity provider
  • Configure IAM Identity Center for multi-account SSO
  • Design a Cognito user pool for customer authentication
  • Explain when to use Cognito user pools vs. identity pools
  • Configure MFA for IAM users and enforce MFA for API calls
  • Troubleshoot authentication failures using CloudTrail
  • Explain the difference between long-term credentials (access keys) and temporary credentials (STS)

Authorization:

  • Write IAM policies with Principal, Action, Resource, and Condition elements
  • Explain the difference between identity-based and resource-based policies
  • Design an ABAC strategy using tags
  • Configure permissions boundaries to limit maximum permissions
  • Write SCPs to restrict account-level actions
  • Use IAM policy simulator to test policy effects
  • Troubleshoot authorization failures using CloudTrail and IAM Access Advisor
  • Explain the policy evaluation logic (Explicit Deny → Explicit Allow → Default Deny)

Advanced Concepts:

  • Design cross-account access using IAM roles
  • Configure session policies to limit temporary credentials
  • Use IAM Access Analyzer to detect external access
  • Implement least privilege using IAM Access Advisor
  • Explain the difference between ABAC and RBAC
  • Design a separation of duties strategy using IAM policies

Practice Questions

Recommended Practice Test Bundles:

  • Domain 4 Bundle 1: Questions 261-310 (covers all Task 4.1, 4.2 topics)
  • Domain 4 Bundle 2: Questions 311-340 (additional practice on weak areas)
  • Identity & Access Bundle: Questions covering IAM, IAM Identity Center, Cognito, STS, Organizations

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • IAM Policy Evaluation Logic (if you struggled with policy precedence questions)
    • ABAC vs. RBAC (if you struggled with scalable permission design questions)
    • Federation and STS (if you struggled with temporary credential questions)
    • Permissions Boundaries and SCPs (if you struggled with guardrail questions)
  • Focus on:
    • Understanding the difference between identity-based and resource-based policies
    • Practicing IAM policy writing with conditions (IP address, MFA, tags)
    • Memorizing the policy evaluation logic (Explicit Deny → Explicit Allow → Default Deny)
    • Understanding when to use ABAC vs. RBAC

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • IAM: Identity and access management (users, groups, roles, policies)
  • IAM Identity Center: Centralized SSO for workforce identities
  • Cognito: Customer identity and access management (user pools, identity pools)
  • STS: Security Token Service (temporary credentials)
  • Organizations: Multi-account management with SCPs
  • IAM Access Analyzer: Detects resources shared with external entities
  • IAM Access Advisor: Shows last accessed services for least privilege

Key Concepts:

  • Identity-Based Policy: Attached to IAM users, groups, or roles
  • Resource-Based Policy: Attached to resources (S3 buckets, KMS keys, etc.)
  • Permissions Boundary: Limits maximum permissions for IAM entities
  • Service Control Policy (SCP): Account-level guardrails in Organizations
  • Session Policy: Limits temporary credentials from AssumeRole or federation
  • ABAC: Attribute-Based Access Control (uses tags)
  • RBAC: Role-Based Access Control (uses roles)
  • Explicit Deny: Always wins in policy evaluation
  • Temporary Credentials: Automatically rotating credentials from STS

Decision Points:

  • Workforce identities → IAM Identity Center (SSO)
  • Customer identities → Cognito (user pools + identity pools)
  • Service-to-service → IAM roles (EC2 instance roles, Lambda execution roles)
  • Cross-account access → IAM roles with trust policies
  • Temporary credentials → STS AssumeRole (always prefer over access keys)
  • MFA enforcement → IAM policy with MFA condition key
  • Scalable permissions → ABAC using tags (not RBAC with many roles)
  • Maximum permissions → Permissions boundaries
  • Account guardrails → Service Control Policies (SCPs)
  • External access detection → IAM Access Analyzer
  • Unused permissions → IAM Access Advisor

Policy Evaluation Logic:

  1. Explicit Deny (always wins)
  2. Explicit Allow (from any policy)
  3. Default Deny (if no explicit allow)

Common Patterns:

  • IAM Identity Center + External IdP → Workforce SSO
  • Cognito User Pools + Identity Pools → Customer authentication + AWS access
  • IAM Role + Trust Policy → Cross-account access
  • STS AssumeRole + Session Policy → Limited temporary credentials
  • ABAC + Tags → Scalable permissions
  • Permissions Boundary + IAM Policy → Delegated permission management
  • SCP + IAM Policy → Account-level guardrails

Chapter Summary

What We Covered

This chapter covered Domain 4: Identity and Access Management (16% of the exam), focusing on two critical task areas:

Task 4.1: Design, implement, and troubleshoot authentication

  • Creating and managing identities (federation, identity providers, IAM Identity Center, Cognito)
  • Long-term credentials (IAM users, access keys) vs temporary credentials (STS, assume role)
  • Troubleshooting authentication using CloudTrail, IAM Access Advisor, and IAM policy simulator
  • Multi-factor authentication (MFA) for users and API calls

Task 4.2: Design, implement, and troubleshoot authorization

  • IAM policy types (managed, inline, identity-based, resource-based, session control, SCPs, permissions boundaries)
  • Policy components (Principal, Action, Resource, Condition)
  • ABAC (Attribute-Based Access Control) and RBAC (Role-Based Access Control) strategies
  • Principle of least privilege and separation of duties
  • Troubleshooting authorization using IAM policy simulator and Access Analyzer

Critical Takeaways

  1. IAM is the foundation of AWS security: Every API call is authenticated and authorized by IAM. Understanding IAM is essential for the exam.

  2. Use temporary credentials, not long-term credentials: Prefer IAM roles with STS temporary credentials over IAM users with access keys. Temporary credentials expire automatically.

  3. IAM Identity Center is the modern way to manage access: Use it for workforce identities (employees) with SSO to multiple AWS accounts. Replaces SAML federation.

  4. Cognito is for customer identities: Use Cognito User Pools for authentication and Cognito Identity Pools for temporary AWS credentials for mobile/web apps.

  5. Policy evaluation follows a specific order: Explicit deny → Organizations SCP → Resource-based policy → Permissions boundary → Session policy → Identity-based policy. Deny always wins.

  6. ABAC scales better than RBAC: Attribute-Based Access Control uses tags to grant permissions dynamically. Role-Based Access Control requires creating a role for each permission set.

  7. Permissions boundaries limit maximum permissions: They don't grant permissions, they limit what identity-based policies can grant. Useful for delegating IAM administration.

  8. SCPs control what accounts can do: Service Control Policies in AWS Organizations set maximum permissions for all principals in an account, including the root user.

  9. MFA adds a second factor: Require MFA for sensitive operations (deleting resources, accessing production). Use MFA condition in policies to enforce.

  10. IAM Access Analyzer finds external access: It identifies resources shared with external entities (S3 buckets, IAM roles, KMS keys, Lambda functions).

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Authentication:

  • Explain the difference between IAM users, IAM roles, and federated identities
  • Configure SAML federation with an external identity provider
  • Set up IAM Identity Center for multi-account SSO
  • Design a Cognito User Pool for customer authentication
  • Use STS AssumeRole to obtain temporary credentials
  • Troubleshoot authentication failures using CloudTrail logs
  • Enforce MFA for sensitive API calls using IAM policy conditions

Authorization:

  • Write an identity-based policy that grants S3 read access
  • Create a resource-based policy for an S3 bucket
  • Explain the difference between managed policies and inline policies
  • Design an ABAC strategy using tags for dynamic permissions
  • Implement a permissions boundary to limit IAM user permissions
  • Create an SCP to prevent account-level actions
  • Use IAM policy simulator to test policy effects
  • Interpret IAM Access Analyzer findings for external access

Policy Evaluation:

  • Explain the order of policy evaluation (deny, SCP, resource-based, etc.)
  • Determine the effective permissions when multiple policies apply
  • Troubleshoot "Access Denied" errors using CloudTrail and policy simulator
  • Identify unintended permissions granted by overly permissive policies
  • Design policies that enforce least privilege

Practice Questions

Try these from your practice test bundles:

  • Domain 4 Bundle 1: Questions 1-25 (focus on authentication and identity management)
  • Domain 4 Bundle 2: Questions 26-50 (focus on authorization and policy design)
  • Identity Access Bundle: Questions covering IAM, IAM Identity Center, Cognito, STS, Organizations
  • Full Practice Test 1: Domain 4 questions (8 questions, 16% of exam)

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review the differences between IAM users, roles, and federated identities
  • Practice writing IAM policies with different policy types
  • Focus on understanding policy evaluation order
  • Revisit ABAC vs RBAC strategies and when to use each

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • IAM: Identity and Access Management for AWS resources
  • IAM Identity Center: SSO for workforce identities across multiple accounts
  • Cognito: Authentication and authorization for customer-facing applications
  • STS: Security Token Service for temporary credentials
  • Organizations: Multi-account management with SCPs
  • IAM Access Analyzer: Identifies resources shared with external entities

Key Concepts:

  • Authentication: Verifying who you are (IAM user, role, federated identity)
  • Authorization: Verifying what you can do (IAM policies)
  • Principal: The entity making the request (user, role, service)
  • Temporary Credentials: Short-lived credentials from STS (15 min to 12 hours)
  • Long-Term Credentials: IAM user access keys (never expire unless rotated)
  • Federation: Using external identity providers (SAML, OIDC) for authentication
  • ABAC: Attribute-Based Access Control using tags for dynamic permissions
  • RBAC: Role-Based Access Control using predefined roles
  • Least Privilege: Granting only the minimum permissions needed
  • Separation of Duties: Ensuring no single person has complete control

Policy Types:

  • Identity-Based: Attached to IAM users, groups, or roles
  • Resource-Based: Attached to resources (S3 buckets, Lambda functions, KMS keys)
  • Permissions Boundary: Limits maximum permissions for identity-based policies
  • Session Policy: Limits permissions when assuming a role
  • SCP: Service Control Policy in Organizations (limits account permissions)
  • Managed Policy: AWS-managed or customer-managed, reusable across identities
  • Inline Policy: Embedded directly in a single identity

Policy Evaluation Order:

  1. Explicit Deny: If any policy has an explicit deny, access is denied
  2. Organizations SCP: If SCP denies, access is denied
  3. Resource-Based Policy: If resource-based policy allows, access is granted (cross-account)
  4. Permissions Boundary: If boundary denies, access is denied
  5. Session Policy: If session policy denies, access is denied
  6. Identity-Based Policy: If identity-based policy allows, access is granted
  7. Default Deny: If no policy allows, access is denied

Decision Points:

  • Need workforce SSO → IAM Identity Center with SAML/OIDC
  • Need customer authentication → Cognito User Pools
  • Need temporary AWS credentials → STS AssumeRole or Cognito Identity Pools
  • Need to limit account permissions → Organizations SCP
  • Need to delegate IAM admin → Permissions boundaries
  • Need dynamic permissions → ABAC with tags
  • Need to find external access → IAM Access Analyzer
  • Need to test policies → IAM policy simulator
  • Need to enforce MFA → IAM policy condition (aws:MultiFactorAuthPresent)

Common Troubleshooting:

  • Access Denied → Check CloudTrail for error, use policy simulator, verify policy evaluation order
  • MFA not working → Check MFA device is registered, policy condition is correct
  • AssumeRole failing → Check trust policy, permissions boundary, SCP
  • Federation not working → Check SAML/OIDC configuration, trust relationship, attribute mapping
  • Unintended permissions → Use IAM Access Analyzer, review resource-based policies

You're now ready for Chapter 5: Data Protection!

The next chapter will teach you how to protect data using encryption and access controls.


Chapter 5: Data Protection (18% of exam)

Chapter Overview

What you'll learn:

  • Encryption for data in transit (TLS, VPN, secure protocols)
  • Encryption for data at rest (KMS, S3, EBS, RDS, DynamoDB)
  • Data lifecycle management and retention policies
  • Secrets and key management (Secrets Manager, KMS, CloudHSM)
  • Certificate management with ACM

Time to complete: 12-15 hours
Prerequisites: Chapter 0 (Fundamentals), Chapter 4 (IAM basics)

Why this domain matters: Data protection is critical for security and compliance. This domain represents 18% of the exam and tests your ability to design encryption strategies, manage cryptographic keys, implement secure data transmission, and enforce data lifecycle policies. Understanding KMS, encryption options, and certificate management is essential.


Section 1: Encryption for Data in Transit

Introduction

The problem: Data transmitted over networks can be intercepted by attackers using packet sniffing, man-in-the-middle attacks, or network taps. Without encryption, sensitive data like passwords, credit cards, and personal information is exposed in plaintext.

The solution: AWS provides multiple mechanisms to encrypt data in transit including TLS/SSL for HTTPS connections, VPN tunnels for site-to-site connectivity, and AWS PrivateLink for private connectivity. These ensure data is encrypted as it moves between clients, services, and data centers.

Why it's tested: The exam tests your understanding of when to use each encryption method, how to enforce encryption requirements, and how to troubleshoot certificate and TLS issues. You must know how to design architectures that protect data in transit.

Core Concepts

TLS/SSL Encryption and Certificate Management

What it is: TLS (Transport Layer Security) is a cryptographic protocol that encrypts data transmitted over networks. SSL (Secure Sockets Layer) is the predecessor to TLS. AWS Certificate Manager (ACM) provides free SSL/TLS certificates for use with AWS services.

Why it exists: HTTP transmits data in plaintext, making it vulnerable to eavesdropping. HTTPS uses TLS to encrypt HTTP traffic, protecting data from interception. ACM simplifies certificate management by automating provisioning, renewal, and deployment.

Real-world analogy: TLS is like sending a letter in a locked box instead of an open envelope. Only the recipient with the key (private key) can open the box and read the letter. Anyone intercepting the box sees only encrypted gibberish.

How TLS works (Detailed step-by-step):

  1. Client Hello: Client initiates connection to server and sends supported TLS versions, cipher suites, and random number.

  2. Server Hello: Server responds with chosen TLS version, cipher suite, and its own random number. Server sends its SSL/TLS certificate containing public key.

  3. Certificate Validation: Client validates server certificate by checking: (a) Certificate is signed by trusted Certificate Authority (CA), (b) Certificate hasn't expired, (c) Certificate domain matches requested domain, (d) Certificate hasn't been revoked.

  4. Key Exchange: Client generates a pre-master secret, encrypts it with server's public key, and sends to server. Only server can decrypt using its private key.

  5. Session Key Generation: Both client and server use the pre-master secret and random numbers to generate identical session keys for symmetric encryption.

  6. Encrypted Communication: All subsequent data is encrypted using session keys with symmetric encryption (AES). Symmetric encryption is much faster than asymmetric encryption used in key exchange.

  7. Connection Termination: When communication ends, session keys are discarded. Each new connection generates new session keys (forward secrecy).

📊 TLS Handshake Sequence Diagram:

sequenceDiagram
    participant Client
    participant Server
    participant CA as Certificate Authority

    Client->>Server: 1. Client Hello (TLS versions, cipher suites)
    Server->>Client: 2. Server Hello (chosen TLS, cipher)
    Server->>Client: 3. Server Certificate (public key)
    Client->>CA: 4. Validate Certificate
    CA-->>Client: 5. Certificate Valid
    Client->>Server: 6. Pre-Master Secret (encrypted with public key)
    Note over Client,Server: Both generate session keys
    Client->>Server: 7. Finished (encrypted with session key)
    Server->>Client: 8. Finished (encrypted with session key)
    Note over Client,Server: Encrypted Communication
    Client<<->>Server: Application Data (AES encrypted)

See: diagrams/06_domain5_tls_handshake.mmd

Diagram Explanation (Detailed):
The TLS handshake diagram shows the complete process of establishing a secure connection between a client and server. In step 1, the client initiates by sending a "Client Hello" message containing supported TLS versions (1.2, 1.3) and cipher suites (encryption algorithms). The server responds in step 2 with its chosen TLS version and cipher suite from the client's list. In step 3, the server sends its SSL/TLS certificate which contains the server's public key and identity information. The client validates this certificate in steps 4-5 by checking with the Certificate Authority (CA) that issued it - verifying the certificate is signed by a trusted CA, hasn't expired, matches the domain, and hasn't been revoked. Once validated, the client generates a random "pre-master secret" in step 6, encrypts it with the server's public key from the certificate, and sends it to the server. Only the server can decrypt this using its private key. Both client and server then independently generate identical session keys using the pre-master secret and random numbers exchanged earlier. They confirm successful key generation in steps 7-8 by sending "Finished" messages encrypted with the new session keys. From this point forward, all application data is encrypted using fast symmetric encryption (typically AES-256) with the session keys. This provides confidentiality (data can't be read), integrity (data can't be modified), and authentication (server identity is verified).

Detailed Example 1: HTTPS Website with ACM Certificate
Imagine you're hosting a corporate website on an Application Load Balancer (ALB) and need to enable HTTPS. You use AWS Certificate Manager to request a free SSL/TLS certificate for your domain "www.example.com". ACM validates domain ownership by sending a verification email or creating a DNS record you must add. Once validated, ACM issues the certificate. You then attach this certificate to your ALB's HTTPS listener on port 443. When users visit https://www.example.com, their browser initiates a TLS handshake with the ALB. The ALB presents the ACM certificate, the browser validates it against trusted CAs (ACM certificates are trusted by all major browsers), and establishes an encrypted connection. All traffic between the user's browser and the ALB is now encrypted with TLS 1.2 or 1.3. The ALB can decrypt the traffic, inspect it, and forward it to backend EC2 instances. ACM automatically renews the certificate before expiration (every 13 months), so you never have to worry about expired certificates causing outages. This provides end-to-end encryption for your website visitors.

Detailed Example 2: API Gateway with Custom Domain and TLS
You're building a REST API using API Gateway and want to use a custom domain name "api.company.com" instead of the default AWS domain. You request an ACM certificate for "api.company.com" in the same region as your API Gateway (or us-east-1 for edge-optimized APIs). After domain validation, you create a custom domain name in API Gateway and select the ACM certificate. API Gateway creates a CloudFront distribution (for edge-optimized) or a regional endpoint. You then create a DNS CNAME record pointing "api.company.com" to the CloudFront or regional domain name. When clients make API calls to https://api.company.com/users, the request goes through CloudFront or the regional endpoint, which terminates the TLS connection using your ACM certificate. The connection from CloudFront/API Gateway to your Lambda functions or backend services uses AWS's internal encrypted network. You can enforce TLS 1.2 minimum by configuring a security policy on the custom domain. This ensures all API traffic is encrypted in transit and uses your branded domain name.

Detailed Example 3: CloudFront with SNI and Multiple Certificates
Your company hosts multiple customer websites on a single CloudFront distribution, each with its own domain and SSL certificate. You use Server Name Indication (SNI), a TLS extension that allows multiple SSL certificates on the same IP address. For each customer domain (customer1.com, customer2.com), you request separate ACM certificates in us-east-1 (CloudFront requires certificates in this region). You configure CloudFront to use SNI by selecting "Custom SSL Certificate" and choosing the appropriate ACM certificate. When a user visits https://customer1.com, their browser includes the domain name in the TLS handshake (SNI extension). CloudFront reads this SNI value and presents the correct certificate for customer1.com. The browser validates the certificate matches the requested domain and establishes the encrypted connection. This allows you to serve multiple HTTPS sites from a single CloudFront distribution without needing dedicated IP addresses (which cost extra). SNI is supported by all modern browsers (IE 11+, Chrome, Firefox, Safari). For legacy browser support, you'd need to use dedicated IP addresses at additional cost.

Must Know (Critical Facts):

  • ACM certificates are free and automatically renew - no manual renewal needed
  • ACM certificates can only be used with AWS services (ALB, CloudFront, API Gateway) - cannot export private keys
  • For CloudFront, ACM certificates must be in us-east-1 region regardless of distribution location
  • TLS 1.2 is the minimum recommended version - TLS 1.0 and 1.1 are deprecated and insecure
  • Perfect Forward Secrecy (PFS) ensures past sessions remain secure even if private key is compromised
  • SNI allows multiple SSL certificates on same IP address - supported by all modern browsers
  • Certificate validation can be done via email or DNS - DNS validation is preferred for automation

When to use (Comprehensive):

  • ✅ Use ACM when: You need SSL/TLS certificates for AWS services (ALB, CloudFront, API Gateway, Elastic Beanstalk)
  • ✅ Use ACM when: You want automatic certificate renewal without manual intervention
  • ✅ Use TLS 1.2+ when: Encrypting any data in transit - never use TLS 1.0/1.1 or SSLv3
  • ✅ Use SNI when: Hosting multiple HTTPS sites on same CloudFront distribution or ALB to save costs
  • ❌ Don't use ACM when: You need to export private keys or use certificates outside AWS
  • ❌ Don't use ACM when: You need certificates for EC2 instances - use Let's Encrypt or commercial CA instead
  • ❌ Don't use self-signed certificates when: Serving public websites - browsers will show security warnings

Limitations & Constraints:

  • ACM certificates cannot be exported - private keys stay within AWS for security
  • ACM certificates limited to 100 per account (can request increase)
  • Domain validation required before certificate issuance - can take minutes to hours
  • Wildcard certificates (*.example.com) supported but don't cover root domain (example.com) - need both
  • Certificate renewal happens 60 days before expiration - ensure DNS/email validation still works

💡 Tips for Understanding:

  • Think of TLS as a secure tunnel - data enters encrypted, travels safely, exits encrypted
  • ACM is like a certificate vending machine - request, validate, use, forget about renewal
  • SNI is like apartment building mailboxes - same address, different names, correct mail delivered
  • Remember: TLS encrypts data in transit, KMS encrypts data at rest - different purposes

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking ACM certificates can be used on EC2 instances directly
    • Why it's wrong: ACM certificates are managed by AWS and private keys cannot be exported
    • Correct understanding: ACM works only with integrated AWS services (ALB, CloudFront, API Gateway). For EC2, use Let's Encrypt or import certificates from commercial CAs
  • Mistake 2: Requesting ACM certificate in wrong region for CloudFront
    • Why it's wrong: CloudFront is a global service but requires certificates in us-east-1
    • Correct understanding: Always request CloudFront ACM certificates in us-east-1, regardless of where your distribution or origin is located
  • Mistake 3: Assuming TLS encryption means end-to-end encryption
    • Why it's wrong: TLS typically terminates at load balancer, traffic to backend may be unencrypted
    • Correct understanding: TLS provides encryption between client and termination point (ALB/CloudFront). For end-to-end encryption, enable TLS from load balancer to backend targets as well

🔗 Connections to Other Topics:

  • Relates to CloudFront because: CloudFront uses ACM certificates for custom domains and enforces HTTPS
  • Builds on IAM by: Certificate validation requires DNS or email access, proving domain ownership
  • Often used with Route 53 to: Create DNS records for certificate validation and custom domain routing
  • Integrates with WAF to: Protect HTTPS endpoints from application-layer attacks after TLS termination

Troubleshooting Common Issues:

  • Issue 1: Certificate validation stuck in "Pending validation" status
    • Solution: Check DNS records for DNS validation or email inbox for email validation. Ensure CNAME record exactly matches ACM requirements
  • Issue 2: Browser shows "Certificate name mismatch" error
    • Solution: Certificate domain must exactly match requested domain. Use wildcard (*.example.com) for subdomains or add multiple domains to certificate
  • Issue 3: CloudFront returns "The request could not be satisfied" error
    • Solution: Ensure ACM certificate is in us-east-1 region and certificate status is "Issued", not "Pending"

VPN and IPsec for Site-to-Site Encryption

What it is: A Virtual Private Network (VPN) creates an encrypted tunnel over the public internet between your on-premises network and AWS VPC. IPsec (Internet Protocol Security) is the protocol suite that provides encryption, authentication, and integrity for VPN connections.

Why it exists: Organizations need to securely connect their on-premises data centers to AWS without exposing traffic to the public internet. VPN provides encrypted connectivity over existing internet connections, avoiding the cost and complexity of dedicated physical connections.

Real-world analogy: A VPN tunnel is like a secure underground tunnel between two buildings. Even though the tunnel goes through public land (the internet), everything inside the tunnel is private and protected. No one outside can see what's being transported through the tunnel.

How IPsec VPN works (Detailed step-by-step):

  1. IKE Phase 1 (Internet Key Exchange): The two VPN endpoints (customer gateway and AWS VPN gateway) negotiate security parameters and authenticate each other. They establish a secure control channel called the IKE Security Association (SA). This uses either pre-shared keys (PSK) or certificates for authentication.

  2. IKE Phase 2: Using the secure channel from Phase 1, the endpoints negotiate IPsec security parameters including encryption algorithms (AES-256), integrity algorithms (SHA-256), and Perfect Forward Secrecy (PFS) settings. They establish IPsec Security Associations for actual data encryption.

  3. Tunnel Establishment: Two IPsec tunnels are created (AWS provides redundancy with two VPN endpoints). Each tunnel has its own encryption keys and security parameters. Traffic can use either tunnel, providing high availability.

  4. Data Encapsulation: When data needs to travel from on-premises to AWS, it's encapsulated in IPsec packets. The original IP packet is encrypted, then wrapped in a new IP header for routing over the internet. This is called tunnel mode.

  5. Encryption and Authentication: Each packet is encrypted using AES (typically AES-256-GCM) and authenticated using HMAC-SHA-256. This ensures confidentiality (can't read), integrity (can't modify), and authenticity (sender verified).

  6. Transmission: Encrypted packets travel over the public internet to the AWS VPN endpoint. Even if intercepted, packets are useless without the encryption keys.

  7. Decryption and Forwarding: AWS VPN gateway decrypts packets, verifies integrity, and forwards original packets to resources in your VPC. Return traffic follows the same process in reverse.

  8. Tunnel Monitoring: Both endpoints continuously monitor tunnel health using Dead Peer Detection (DPD). If a tunnel fails, traffic automatically switches to the backup tunnel within seconds.

📊 Site-to-Site VPN Architecture Diagram:

graph TB
    subgraph "On-Premises Data Center"
        DC[Corporate Network]
        CGW[Customer Gateway Device]
        DC --> CGW
    end

    subgraph "Internet"
        INT[Public Internet<br/>Encrypted IPsec Tunnels]
    end

    subgraph "AWS VPC"
        VGW[Virtual Private Gateway]
        PRIV[Private Subnet<br/>10.0.1.0/24]
        EC2[EC2 Instances]
        RDS[(RDS Database)]
        
        VGW --> PRIV
        PRIV --> EC2
        PRIV --> RDS
    end

    CGW -.IPsec Tunnel 1<br/>AES-256 Encrypted.-> INT
    CGW -.IPsec Tunnel 2<br/>AES-256 Encrypted.-> INT
    INT -.-> VGW

    style CGW fill:#fff3e0
    style VGW fill:#e1f5fe
    style INT fill:#ffebee
    style EC2 fill:#c8e6c9
    style RDS fill:#c8e6c9

See: diagrams/06_domain5_site_to_site_vpn.mmd

Diagram Explanation (Detailed):
The Site-to-Site VPN diagram shows how on-premises networks securely connect to AWS VPCs. The Corporate Network connects to a Customer Gateway (CGW) device - typically a physical router or firewall that supports IPsec. The CGW establishes two redundant IPsec tunnels (orange dashed lines) over the public internet to AWS's Virtual Private Gateway (VGW) attached to your VPC. Both tunnels use AES-256 encryption to protect all data in transit. The red "Public Internet" cloud represents the untrusted network where encrypted packets travel - even though it's public, the encryption makes the data unreadable to anyone intercepting it. The VGW (blue) acts as the AWS-side VPN endpoint, decrypting traffic and routing it to private subnets in your VPC. Resources like EC2 instances and RDS databases (green) in private subnets can communicate with on-premises systems as if they were on the same local network. The dual tunnels provide high availability - if one tunnel fails due to internet routing issues, traffic automatically fails over to the second tunnel within seconds. This architecture allows secure hybrid cloud connectivity without expensive dedicated connections.

Detailed Example 1: Connecting Corporate Data Center to AWS
Your company has a data center in Chicago and wants to securely connect it to an AWS VPC in us-east-1 for hybrid cloud operations. You deploy a Cisco ASA firewall as your Customer Gateway device. In AWS, you create a Virtual Private Gateway and attach it to your VPC. You then create a Site-to-Site VPN connection, specifying your Customer Gateway's public IP address (203.0.113.5) and a pre-shared key for authentication. AWS provides you with a configuration file containing two tunnel endpoints (AWS provides two for redundancy), pre-shared keys, and recommended IPsec parameters. You configure your Cisco ASA with these settings, establishing two IPsec tunnels. You update your VPC route table to route traffic destined for your on-premises network (192.168.0.0/16) through the Virtual Private Gateway. Similarly, you configure your on-premises router to route AWS traffic (10.0.0.0/16) through the VPN tunnels. Now, when an application server in Chicago needs to access an RDS database in AWS, the traffic is automatically encrypted by the Cisco ASA, sent through the IPsec tunnel over the internet, decrypted by the VGW, and delivered to the RDS instance. All traffic is encrypted with AES-256, and the connection provides 1.25 Gbps throughput per tunnel.

Detailed Example 2: Accelerated VPN with Global Accelerator
Your company has offices in Singapore and Sydney that need low-latency access to AWS resources in us-west-2. Standard Site-to-Site VPN routes traffic over the public internet, which can have variable latency and packet loss. You enable VPN acceleration by creating an Accelerated Site-to-Site VPN connection. This uses AWS Global Accelerator to route VPN traffic over AWS's private global network instead of the public internet. When you create the VPN connection, you select "Enable acceleration". AWS provides you with two static anycast IP addresses (instead of regional IPs) that are advertised from AWS edge locations worldwide. Your Singapore office's Customer Gateway connects to these anycast IPs. Traffic enters AWS's network at the nearest edge location (Singapore), travels over AWS's private fiber network to us-west-2, then connects to your VPC through the VGW. This reduces latency by 30-50% compared to public internet routing and provides more consistent performance. The IPsec encryption remains the same, but the underlying network path is optimized. This is ideal for latency-sensitive applications like VoIP, video conferencing, or real-time data replication.

Detailed Example 3: VPN with Transit Gateway for Multi-VPC Connectivity
Your organization has 20 VPCs across multiple AWS regions and needs to connect all of them to your on-premises data center. Instead of creating 20 separate VPN connections (complex and expensive), you use AWS Transit Gateway as a central hub. You create a Transit Gateway in your primary region and attach all 20 VPCs to it. You then create a single Site-to-Site VPN connection from your Customer Gateway to the Transit Gateway (instead of individual VGWs). The Transit Gateway acts as a regional router, allowing your on-premises network to reach all 20 VPCs through a single VPN connection. You configure route tables in the Transit Gateway to control which VPCs can communicate with on-premises and with each other. For example, production VPCs can access on-premises databases, but development VPCs cannot. This architecture reduces the number of VPN connections from 20 to 1, simplifies routing, and provides centralized control. You can also enable ECMP (Equal Cost Multi-Path) on the Transit Gateway to use multiple VPN tunnels simultaneously, increasing throughput beyond the 1.25 Gbps per-tunnel limit.

Must Know (Critical Facts):

  • AWS Site-to-Site VPN provides two tunnels for high availability - always configure both on your Customer Gateway
  • Each VPN tunnel supports up to 1.25 Gbps throughput - use ECMP with Transit Gateway for higher bandwidth
  • IPsec uses AES-256-GCM for encryption and SHA-256 for authentication by default
  • VPN connections charge $0.05 per hour plus data transfer costs - cheaper than Direct Connect for low-volume traffic
  • Dead Peer Detection (DPD) timeout is 30 seconds - tunnels failover quickly if one endpoint becomes unreachable
  • Pre-shared keys must be strong (minimum 20 characters) - AWS generates secure keys automatically
  • VPN over Direct Connect provides encrypted connectivity over dedicated connection - combines benefits of both

When to use (Comprehensive):

  • ✅ Use Site-to-Site VPN when: You need secure connectivity to AWS but don't require dedicated bandwidth
  • ✅ Use Site-to-Site VPN when: You need quick setup (minutes vs weeks for Direct Connect)
  • ✅ Use Site-to-Site VPN when: Your bandwidth requirements are under 1.25 Gbps per connection
  • ✅ Use Accelerated VPN when: You need low latency from distant geographic locations
  • ✅ Use VPN with Transit Gateway when: Connecting multiple VPCs to on-premises through single connection
  • ❌ Don't use VPN when: You need guaranteed bandwidth over 10 Gbps - use Direct Connect instead
  • ❌ Don't use VPN when: You have strict latency requirements under 10ms - use Direct Connect instead
  • ❌ Don't use VPN when: Internet connectivity is unreliable - VPN requires stable internet connection

Limitations & Constraints:

  • Maximum throughput: 1.25 Gbps per tunnel (can use multiple tunnels with ECMP for higher throughput)
  • VPN depends on internet quality - latency and packet loss vary based on internet path
  • Customer Gateway must support IPsec with specific parameters (IKEv2, AES-256, SHA-256)
  • Cannot use overlapping IP address ranges between on-premises and VPC
  • VPN connection limit: 10 per VPC (can request increase)

💡 Tips for Understanding:

  • Think of IPsec as a secure envelope - data goes in, gets sealed with encryption, travels safely, gets opened at destination
  • Remember: VPN = encrypted tunnel over internet, Direct Connect = dedicated physical connection (not encrypted by default)
  • Two tunnels = high availability - if one fails, the other takes over automatically
  • Accelerated VPN = VPN + Global Accelerator = faster, more reliable connectivity

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Configuring only one VPN tunnel on Customer Gateway
    • Why it's wrong: AWS provides two tunnels for redundancy, but you must configure both on your side
    • Correct understanding: Always configure both tunnels on your Customer Gateway. If you only configure one, you lose high availability and will experience downtime during AWS maintenance
  • Mistake 2: Assuming VPN provides dedicated bandwidth like Direct Connect
    • Why it's wrong: VPN runs over the public internet with shared bandwidth and variable performance
    • Correct understanding: VPN throughput and latency depend on your internet connection quality. For guaranteed performance, use Direct Connect or VPN over Direct Connect
  • Mistake 3: Thinking Direct Connect is encrypted by default
    • Why it's wrong: Direct Connect is a private connection but doesn't encrypt traffic automatically
    • Correct understanding: Direct Connect provides private connectivity but not encryption. For encrypted Direct Connect, run a VPN connection over the Direct Connect link (VPN over Direct Connect)

🔗 Connections to Other Topics:

  • Relates to Direct Connect because: VPN can run over Direct Connect for encrypted dedicated connectivity
  • Builds on VPC by: VPN connects on-premises networks to VPCs through Virtual Private Gateway
  • Often used with Transit Gateway to: Centralize VPN connectivity for multiple VPCs
  • Integrates with Route 53 to: Provide DNS resolution between on-premises and AWS resources

Troubleshooting Common Issues:

  • Issue 1: VPN tunnel status shows "DOWN"
    • Solution: Check Customer Gateway configuration matches AWS-provided settings. Verify firewall allows UDP 500 (IKE) and IP protocol 50 (ESP). Check pre-shared key matches exactly
  • Issue 2: VPN tunnel connects but no traffic flows
    • Solution: Verify route tables on both sides. AWS VPC route table must route on-premises CIDR to VGW. On-premises router must route AWS CIDR to VPN tunnel
  • Issue 3: Intermittent VPN disconnections
    • Solution: Check internet connection stability. Adjust DPD timeout settings. Consider Accelerated VPN for more reliable connectivity over AWS network

Secure Remote Access with Systems Manager Session Manager

What it is: AWS Systems Manager Session Manager is a fully managed service that provides secure, browser-based shell access to EC2 instances and on-premises servers without requiring SSH keys, bastion hosts, or open inbound ports.

Why it exists: Traditional SSH access requires opening port 22 to the internet (security risk), managing SSH keys (operational overhead), and deploying bastion hosts (additional cost and complexity). Session Manager eliminates these requirements while providing better security, auditability, and ease of use.

Real-world analogy: Session Manager is like having a secure video call system built into your office building. Instead of giving everyone physical keys (SSH keys) and leaving doors unlocked (open ports), employees can request access through a secure system that verifies their identity and logs every interaction.

How Session Manager works (Detailed step-by-step):

  1. Agent Installation: The SSM Agent is installed on EC2 instances (pre-installed on Amazon Linux 2, Ubuntu, Windows AMIs). The agent runs as a background service and periodically checks with Systems Manager service for commands.

  2. IAM Authentication: When a user wants to start a session, they authenticate using their IAM credentials (not SSH keys). IAM policies control who can start sessions and on which instances.

  3. Session Request: The user initiates a session through AWS Console, CLI, or SDK. The request includes the target instance ID and is sent to the Systems Manager service in the AWS region.

  4. Agent Communication: The SSM Agent on the target instance polls the Systems Manager service over HTTPS (port 443 outbound). It receives the session request and establishes a secure WebSocket connection back to the service.

  5. Encrypted Tunnel: All session data (commands and output) is encrypted using TLS 1.2 and transmitted through the WebSocket connection. No inbound ports need to be open on the instance - all communication is outbound from the instance to AWS.

  6. Session Execution: Commands entered by the user are sent through the encrypted tunnel to the SSM Agent, which executes them on the instance. Output is sent back through the same encrypted tunnel.

  7. Session Logging: All session activity (commands, output, start/end times) can be logged to CloudWatch Logs or S3 for audit purposes. This provides complete visibility into who accessed what and when.

  8. Session Termination: When the user ends the session or the session times out (default 20 minutes of inactivity), the WebSocket connection is closed and the session is terminated.

📊 Session Manager Architecture Diagram:

graph TB
    subgraph "User Access"
        USER[Administrator]
        CONSOLE[AWS Console/CLI]
        USER --> CONSOLE
    end

    subgraph "AWS Systems Manager"
        SSM[Systems Manager Service]
        IAM[IAM Authentication]
        CONSOLE --> IAM
        IAM --> SSM
    end

    subgraph "VPC - Private Subnet"
        EC2[EC2 Instance<br/>No Public IP]
        AGENT[SSM Agent]
        EC2 --> AGENT
    end

    subgraph "Logging & Audit"
        CWL[CloudWatch Logs]
        S3[S3 Bucket]
    end

    AGENT -.HTTPS Port 443<br/>Outbound Only.-> SSM
    SSM -.Encrypted WebSocket<br/>TLS 1.2.-> AGENT
    SSM --> CWL
    SSM --> S3

    style USER fill:#e1f5fe
    style SSM fill:#fff3e0
    style EC2 fill:#c8e6c9
    style AGENT fill:#c8e6c9
    style CWL fill:#f3e5f5
    style S3 fill:#f3e5f5

See: diagrams/06_domain5_session_manager.mmd

Diagram Explanation (Detailed):
The Session Manager architecture diagram shows how secure remote access works without SSH keys or open inbound ports. An Administrator (blue) accesses instances through the AWS Console or CLI, which authenticates them via IAM. The Systems Manager service (orange) validates permissions and coordinates the session. The EC2 instance (green) sits in a private subnet with no public IP address and no inbound security group rules. The SSM Agent running on the instance makes outbound HTTPS connections (port 443) to the Systems Manager service - this is the only network requirement. When a session starts, an encrypted WebSocket tunnel (TLS 1.2) is established between the SSM Agent and Systems Manager service. All commands and output flow through this encrypted tunnel. The instance never accepts inbound connections, eliminating the attack surface. Session activity is logged to CloudWatch Logs and/or S3 (purple) for compliance and audit purposes. This architecture provides secure access without bastion hosts, SSH keys, or open ports, while maintaining complete audit trails of all access.

Detailed Example 1: Replacing SSH Access with Session Manager
Your company has 50 EC2 instances in private subnets that developers need to access for troubleshooting. Previously, you used a bastion host with SSH keys, but managing keys and bastion host security was challenging. You decide to implement Session Manager. First, you ensure all instances have the SSM Agent installed (it's pre-installed on Amazon Linux 2). You create an IAM role with the AmazonSSMManagedInstanceCore managed policy and attach it to all EC2 instances. This allows the SSM Agent to communicate with Systems Manager. You create an IAM policy that allows developers to start sessions: ssm:StartSession on specific instance resources. You remove the bastion host and close port 22 in all security groups. Now, developers access instances by running aws ssm start-session --target i-1234567890abcdef0 from their laptops. They authenticate with their IAM credentials (MFA required), and Session Manager establishes an encrypted connection to the instance. No SSH keys to manage, no bastion host to maintain, and all access is logged to CloudWatch Logs. You can see exactly who accessed which instance, when, and what commands they ran.

Detailed Example 2: Port Forwarding for RDS Access
Your RDS database is in a private subnet with no public access, and you need to connect from your local machine for database administration. Instead of creating a bastion host or VPN, you use Session Manager port forwarding. You have an EC2 instance in the same VPC as your RDS database with SSM Agent installed. You run: aws ssm start-session --target i-1234567890abcdef0 --document-name AWS-StartPortForwardingSessionToRemoteHost --parameters '{"host":["mydb.abc123.us-east-1.rds.amazonaws.com"],"portNumber":["3306"],"localPortNumber":["9999"]}'. This command creates an encrypted tunnel from your local port 9999, through the EC2 instance, to the RDS database on port 3306. You can now connect your MySQL client to localhost:9999, and traffic is securely forwarded to the RDS database. All traffic through the tunnel is encrypted with TLS 1.2. When you're done, you terminate the session and the tunnel closes. This provides secure database access without exposing RDS to the internet or maintaining a bastion host.

Detailed Example 3: Session Manager with Logging and Compliance
Your organization has strict compliance requirements that mandate logging all administrative access to production systems. You configure Session Manager to log all session activity. You create an S3 bucket with encryption enabled and a CloudWatch Logs log group. In Systems Manager Session Manager preferences, you enable session logging and specify the S3 bucket and CloudWatch log group. You also enable KMS encryption for session data using a customer-managed key. Now, every time someone starts a session, all commands and output are encrypted with your KMS key and stored in both S3 and CloudWatch Logs. You create CloudWatch metric filters to alert on suspicious commands like rm -rf, iptables, or passwd. You use CloudWatch Logs Insights to query session logs: "Show me all sessions where user X accessed production instances in the last 30 days." For compliance audits, you provide the S3 bucket with complete session transcripts, proving who accessed what, when, and what they did. The logs are immutable (using S3 Object Lock) and retained for 7 years per compliance requirements.

Must Know (Critical Facts):

  • Session Manager requires NO inbound ports open - all communication is outbound HTTPS (port 443) from instance to AWS
  • SSM Agent must be installed and running on instances - pre-installed on Amazon Linux 2, Ubuntu, Windows Server 2016+
  • IAM instance role with AmazonSSMManagedInstanceCore policy required for SSM Agent to function
  • Session Manager supports port forwarding to access private resources (RDS, ElastiCache) without bastion hosts
  • All session activity can be logged to CloudWatch Logs and S3 for audit and compliance
  • Session Manager works with instances in private subnets with no public IP addresses
  • MFA can be enforced for session access using IAM condition keys (aws:MultiFactorAuthPresent)

When to use (Comprehensive):

  • ✅ Use Session Manager when: You need secure shell access to EC2 instances without SSH keys
  • ✅ Use Session Manager when: You want to eliminate bastion hosts and reduce attack surface
  • ✅ Use Session Manager when: You need complete audit logs of all administrative access
  • ✅ Use Session Manager when: Accessing instances in private subnets without VPN or Direct Connect
  • ✅ Use port forwarding when: You need to access private resources (RDS, ElastiCache) from your local machine
  • ❌ Don't use Session Manager when: You need to transfer large files - use S3 or SFTP instead
  • ❌ Don't use Session Manager when: You need persistent connections for long-running processes - sessions timeout after inactivity

Limitations & Constraints:

  • Session timeout: 20 minutes of inactivity by default (configurable up to 60 minutes)
  • Maximum session duration: 60 minutes (can be extended by user activity)
  • SSM Agent requires outbound internet access or VPC endpoints for Systems Manager
  • Port forwarding limited to TCP protocols - UDP not supported
  • Cannot transfer files directly through sessions - use S3 or port forwarding with SCP/SFTP

💡 Tips for Understanding:

  • Think of Session Manager as "SSH without SSH" - same functionality, better security
  • Remember: Outbound only = no inbound ports = smaller attack surface
  • Port forwarding = secure tunnel to private resources without VPN
  • Session logging = complete audit trail for compliance

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking Session Manager requires VPN or Direct Connect for private instances
    • Why it's wrong: Session Manager works over the internet using outbound HTTPS connections
    • Correct understanding: Instances only need outbound internet access (via NAT Gateway or VPC endpoints). No VPN required. For fully private access, use VPC endpoints for Systems Manager
  • Mistake 2: Forgetting to attach IAM instance role to EC2 instances
    • Why it's wrong: SSM Agent cannot authenticate with Systems Manager without proper IAM role
    • Correct understanding: Every instance must have an IAM instance role with AmazonSSMManagedInstanceCore policy. Without this, the instance won't appear in Session Manager
  • Mistake 3: Assuming Session Manager replaces all SSH use cases
    • Why it's wrong: Session Manager is for interactive shell access, not file transfers or persistent connections
    • Correct understanding: Use Session Manager for shell access and troubleshooting. For file transfers, use S3. For persistent connections, use SSH with proper security controls

🔗 Connections to Other Topics:

  • Relates to IAM because: Session Manager uses IAM for authentication and authorization instead of SSH keys
  • Builds on VPC by: Allowing access to instances in private subnets without bastion hosts
  • Often used with CloudWatch to: Log all session activity for audit and compliance
  • Integrates with KMS to: Encrypt session data and logs with customer-managed keys

Troubleshooting Common Issues:

  • Issue 1: Instance doesn't appear in Session Manager console
    • Solution: Verify SSM Agent is installed and running. Check IAM instance role has AmazonSSMManagedInstanceCore policy. Ensure instance has outbound internet access or VPC endpoints for Systems Manager
  • Issue 2: "Session Manager plugin not found" error
    • Solution: Install Session Manager plugin on your local machine: https://docs.aws.amazon.com/systems-manager/latest/userguide/session-manager-working-with-install-plugin.html
  • Issue 3: Port forwarding fails to connect to remote host
    • Solution: Verify EC2 instance can reach the remote host (check security groups, NACLs, route tables). Ensure remote host port is correct and service is listening

Section 2: Confidentiality and Integrity for Data at Rest

Introduction

The problem: Data stored on disks, databases, and object storage is vulnerable to unauthorized access if physical media is stolen, snapshots are shared, or access controls are misconfigured. Unencrypted data at rest can be read by anyone with access to the storage medium.

The solution: AWS provides encryption at rest for all storage services using AES-256 encryption. Data is encrypted before being written to disk and decrypted when read. Encryption keys are managed by AWS Key Management Service (KMS), providing centralized key management, rotation, and access control.

Why it's tested: The exam tests your ability to select appropriate encryption methods, configure encryption for various AWS services, implement key management strategies, and prevent unauthorized data access. You must understand the differences between AWS-managed keys, customer-managed keys, and customer-provided keys.

Core Concepts

Encryption Techniques and Key Management

What it is: Encryption at rest transforms data into ciphertext using encryption algorithms and keys. AWS supports server-side encryption (AWS encrypts data) and client-side encryption (you encrypt data before sending to AWS). Keys are managed through AWS KMS, which provides secure key storage, rotation, and access control.

Why it exists: Regulatory requirements (HIPAA, PCI-DSS, GDPR) mandate encryption of sensitive data at rest. Encryption protects against physical theft of storage devices, unauthorized snapshots, and accidental data exposure. Key management ensures only authorized users and services can decrypt data.

Real-world analogy: Encryption at rest is like storing documents in a locked safe. Even if someone steals the safe (storage device), they can't read the documents without the key. KMS is like a secure key management system where keys are stored in a vault, access is logged, and keys can be rotated regularly.

How encryption at rest works (Detailed step-by-step):

  1. Key Creation: You create a KMS key (formerly called Customer Master Key or CMK) in AWS KMS. This is a logical key that never leaves KMS. You define key policies that control who can use the key for encryption and decryption.

  2. Data Key Generation: When you need to encrypt data, the AWS service (S3, EBS, RDS) calls KMS to generate a data encryption key (DEK). KMS generates a plaintext DEK and an encrypted copy of the DEK using your KMS key.

  3. Data Encryption: The AWS service uses the plaintext DEK to encrypt your data using AES-256-GCM (Galois/Counter Mode). This is fast symmetric encryption suitable for large amounts of data.

  4. Key Storage: The encrypted data is stored along with the encrypted DEK. The plaintext DEK is immediately discarded from memory after encryption. Only the encrypted DEK is stored.

  5. Data Decryption Request: When you need to read the data, the AWS service retrieves the encrypted DEK and sends it to KMS for decryption.

  6. DEK Decryption: KMS decrypts the encrypted DEK using your KMS key (after checking permissions). KMS returns the plaintext DEK to the service.

  7. Data Decryption: The service uses the plaintext DEK to decrypt your data. The plaintext DEK is kept in memory only during the operation and then discarded.

  8. Envelope Encryption: This process is called envelope encryption - data is encrypted with a DEK, and the DEK is encrypted with a KMS key. This provides performance (symmetric encryption for data) and security (keys managed by KMS).

📊 Envelope Encryption Diagram:

sequenceDiagram
    participant App as Application/Service
    participant KMS as AWS KMS
    participant Storage as Storage (S3/EBS/RDS)

    Note over App,Storage: Encryption Process
    App->>KMS: 1. GenerateDataKey(KMS Key ID)
    KMS-->>App: 2. Plaintext DEK + Encrypted DEK
    App->>App: 3. Encrypt data with Plaintext DEK (AES-256)
    App->>Storage: 4. Store encrypted data + Encrypted DEK
    App->>App: 5. Discard Plaintext DEK from memory

    Note over App,Storage: Decryption Process
    App->>Storage: 6. Retrieve encrypted data + Encrypted DEK
    App->>KMS: 7. Decrypt(Encrypted DEK)
    KMS-->>App: 8. Plaintext DEK (after permission check)
    App->>App: 9. Decrypt data with Plaintext DEK
    App->>App: 10. Discard Plaintext DEK from memory

See: diagrams/06_domain5_envelope_encryption.mmd

Diagram Explanation (Detailed):
The envelope encryption diagram shows how AWS services encrypt data at rest using KMS. In the encryption process (top half), an application or AWS service requests a data encryption key from KMS by calling GenerateDataKey with a KMS key ID. KMS generates a random 256-bit data encryption key (DEK) and returns both a plaintext version and an encrypted version (encrypted with the KMS key). The service uses the plaintext DEK to encrypt the actual data using fast AES-256-GCM symmetric encryption. The encrypted data and the encrypted DEK are stored together in storage (S3, EBS, RDS). The plaintext DEK is immediately discarded from memory for security. In the decryption process (bottom half), when data needs to be read, the service retrieves both the encrypted data and the encrypted DEK from storage. It sends the encrypted DEK to KMS for decryption. KMS checks IAM permissions and key policies, then decrypts the encrypted DEK using the KMS key and returns the plaintext DEK. The service uses this plaintext DEK to decrypt the data, then immediately discards the plaintext DEK from memory. This envelope encryption approach provides performance (symmetric encryption for data), security (keys never leave KMS), and scalability (each object has its own DEK).

Detailed Example 1: S3 Bucket Encryption with SSE-KMS
Your company stores customer financial records in an S3 bucket and needs encryption with audit trails. You enable server-side encryption with AWS KMS (SSE-KMS) on the bucket. You create a customer-managed KMS key named "FinancialRecordsKey" with a key policy that allows only the Finance team's IAM role to decrypt objects. You enable default encryption on the S3 bucket using this KMS key. When a user uploads a file, S3 automatically calls KMS to generate a data encryption key. KMS generates a unique DEK for this object, encrypts it with your KMS key, and returns both versions to S3. S3 encrypts the file with the plaintext DEK using AES-256-GCM, stores the encrypted file and encrypted DEK together, and discards the plaintext DEK. Every encryption and decryption operation is logged in CloudTrail, showing who accessed what data and when. When a Finance team member downloads the file, S3 sends the encrypted DEK to KMS. KMS checks that the user's IAM role has permission, decrypts the DEK, and returns it to S3. S3 decrypts the file and streams it to the user. If an unauthorized user tries to download the file, KMS denies the decryption request and the download fails. This provides encryption at rest with fine-grained access control and complete audit trails.

Detailed Example 2: EBS Volume Encryption for EC2
You're launching EC2 instances that process sensitive healthcare data and need encrypted EBS volumes. You create a customer-managed KMS key named "HealthcareDataKey" with a key policy that allows only the Healthcare application's IAM role to use it. When launching an EC2 instance, you select "Encrypt this volume" and choose your KMS key. AWS creates an encrypted EBS volume. When the instance writes data to the volume, the EBS service calls KMS to generate a volume data encryption key (unique per volume). This DEK is cached in memory on the EC2 host for performance. All data written to the EBS volume is encrypted with AES-256-XTS (optimized for block storage) using this DEK before being written to disk. The encrypted DEK is stored with the volume metadata. When you create a snapshot of the volume, the snapshot is automatically encrypted with the same KMS key. If you share the snapshot with another AWS account, they cannot use it unless you grant them permission to use your KMS key. When you create a new volume from the encrypted snapshot, it's also encrypted. This ensures data remains encrypted throughout its lifecycle - on volumes, in snapshots, and when copied across regions.

Detailed Example 3: RDS Database Encryption with Automatic Key Rotation
Your company runs a PostgreSQL database on RDS storing customer personal information. You enable encryption at rest when creating the RDS instance, selecting a customer-managed KMS key named "CustomerDBKey". RDS encrypts the database storage, automated backups, read replicas, and snapshots using this key. You enable automatic key rotation on the KMS key. Every year, AWS automatically creates a new cryptographic key material and associates it with your KMS key ID. Old key material is retained for decrypting existing data. When new data is written to the database, RDS calls KMS to generate a data encryption key. KMS uses the current (rotated) key material to encrypt the DEK. Existing data remains encrypted with DEKs that were encrypted with older key material. When you read old data, KMS automatically uses the correct historical key material to decrypt the DEK. This rotation happens transparently without downtime or re-encryption of existing data. If you need to share a database snapshot with another account, you must grant them permission to use your KMS key. You can also copy the snapshot and re-encrypt it with a different KMS key for the destination account.

Must Know (Critical Facts):

  • AWS KMS keys never leave KMS - they cannot be exported or viewed
  • Envelope encryption: Data encrypted with DEK, DEK encrypted with KMS key
  • Automatic key rotation creates new key material yearly but retains old material for decryption
  • SSE-S3 uses AWS-managed keys (free), SSE-KMS uses customer-managed keys (charged per API call)
  • Customer-managed keys provide audit trails in CloudTrail - every encrypt/decrypt operation logged
  • Encrypted EBS volumes can only be attached to instance types that support encryption
  • RDS encryption must be enabled at creation time - cannot encrypt existing unencrypted database

When to use (Comprehensive):

  • ✅ Use SSE-KMS when: You need audit trails of encryption/decryption operations
  • ✅ Use SSE-KMS when: You need fine-grained access control over who can decrypt data
  • ✅ Use customer-managed keys when: You need to control key rotation, deletion, and policies
  • ✅ Use automatic key rotation when: You want annual key material rotation without operational overhead
  • ✅ Use SSE-S3 when: You need encryption but don't require audit trails or custom key policies
  • ❌ Don't use SSE-KMS when: You have very high request rates (>5,500 requests/second) - use SSE-S3 or request KMS quota increase
  • ❌ Don't use client-side encryption when: You need AWS services to process data (Athena, Redshift Spectrum) - they can't decrypt client-side encrypted data

Limitations & Constraints:

  • KMS API rate limits: 5,500 requests/second (shared across all operations) - can request increase
  • KMS keys are regional - must create keys in each region where you need encryption
  • Encrypted snapshots cannot be made public - encryption prevents public sharing
  • Cannot change encryption key after resource creation - must create new resource with different key
  • Cross-region encrypted snapshot copy requires KMS key in destination region

💡 Tips for Understanding:

  • Think of KMS as a secure key vault - keys go in, never come out, but can be used for encryption/decryption
  • Envelope encryption = two layers: data encrypted with DEK, DEK encrypted with KMS key
  • Remember: SSE-S3 = AWS manages everything, SSE-KMS = you control keys and policies
  • Automatic rotation = new key material, same key ID, old material retained for decryption

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking you can export KMS keys for use outside AWS
    • Why it's wrong: KMS keys are designed to never leave AWS for security
    • Correct understanding: KMS keys are used only within AWS. For external encryption, use client-side encryption with your own keys, or import your keys into KMS
  • Mistake 2: Assuming automatic key rotation re-encrypts all existing data
    • Why it's wrong: Rotation creates new key material for future operations, doesn't touch existing data
    • Correct understanding: Automatic rotation creates new cryptographic material for new encrypt operations. Old material is retained to decrypt existing data. No re-encryption occurs
  • Mistake 3: Forgetting that encrypted resources cannot be made public
    • Why it's wrong: Encryption requires KMS key access, which cannot be granted to anonymous users
    • Correct understanding: Encrypted EBS snapshots, RDS snapshots, and S3 objects with SSE-KMS cannot be made public. To share, grant specific AWS accounts permission to use your KMS key

🔗 Connections to Other Topics:

  • Relates to IAM because: KMS key policies and IAM policies together control who can use keys
  • Builds on CloudTrail by: Logging all KMS API calls for audit and compliance
  • Often used with S3 to: Encrypt objects at rest with SSE-KMS or SSE-S3
  • Integrates with Organizations to: Enforce encryption across all accounts using SCPs

Troubleshooting Common Issues:

  • Issue 1: "Access Denied" when trying to decrypt S3 object
    • Solution: Check both S3 bucket policy and KMS key policy. User needs s3:GetObject on bucket AND kms:Decrypt on KMS key
  • Issue 2: Cannot create encrypted EBS volume from unencrypted snapshot
    • Solution: Copy the snapshot and enable encryption during copy, specifying a KMS key. Then create volume from encrypted snapshot
  • Issue 3: KMS API rate limit exceeded errors
    • Solution: Reduce request rate, use SSE-S3 instead of SSE-KMS for high-throughput workloads, or request KMS quota increase

S3 Data Protection Features

What it is: Amazon S3 provides multiple features to protect data integrity and prevent unauthorized modifications or deletions. These include S3 Object Lock (WORM storage), S3 Versioning (retain multiple versions), MFA Delete (require MFA for deletions), and S3 Block Public Access (prevent accidental public exposure).

Why it exists: Regulatory compliance (SEC 17a-4, FINRA, HIPAA) requires immutable storage where data cannot be modified or deleted for specified retention periods. Organizations need protection against accidental deletions, ransomware attacks, and insider threats. S3 provides these protections at the storage layer.

Real-world analogy: S3 Object Lock is like a time-locked safe deposit box - once you put documents in and set the timer, no one (not even you) can remove or modify them until the time expires. S3 Versioning is like keeping every draft of a document - if you accidentally delete or overwrite the current version, you can always retrieve an earlier version.

How S3 Object Lock works (Detailed step-by-step):

  1. Bucket Configuration: You enable Object Lock when creating an S3 bucket (cannot be enabled on existing buckets). This automatically enables versioning, as Object Lock works at the version level.

  2. Retention Mode Selection: You choose between two retention modes:

    • Compliance Mode: No one, including root account, can delete or modify objects during retention period. Retention period cannot be shortened. Used for regulatory compliance.
    • Governance Mode: Users with special permissions (s3:BypassGovernanceRetention) can delete objects or shorten retention. Used for internal policies with override capability.
  3. Retention Period: You set a retention period (days or years) for objects. During this period, objects are protected from deletion and modification. You can extend retention periods but cannot shorten them (in Compliance mode).

  4. Object Upload: When you upload an object, you can specify retention settings (mode and period) or use bucket default retention settings. S3 stores the retention metadata with the object version.

  5. Protection Enforcement: During the retention period, any attempt to delete or overwrite the object version fails with an Access Denied error. Even the root account cannot bypass Compliance mode protection.

  6. Legal Hold: Independently of retention periods, you can place a legal hold on objects. Legal holds prevent deletion indefinitely until explicitly removed. Used for litigation or investigations.

  7. Retention Expiration: After the retention period expires, objects can be deleted normally (unless a legal hold is in place). Objects don't automatically delete - you must explicitly delete them or use lifecycle policies.

  8. Audit Trail: All Object Lock operations (setting retention, placing legal holds, deletion attempts) are logged in CloudTrail for compliance auditing.

📊 S3 Object Lock Architecture Diagram:

graph TB
    subgraph "S3 Bucket with Object Lock"
        BUCKET[S3 Bucket<br/>Object Lock Enabled<br/>Versioning Enabled]
        
        subgraph "Object Versions"
            V1[Version 1<br/>Compliance Mode<br/>Retain until 2025-12-31]
            V2[Version 2<br/>Governance Mode<br/>Retain until 2024-06-30]
            V3[Version 3<br/>Legal Hold Active]
        end
        
        BUCKET --> V1
        BUCKET --> V2
        BUCKET --> V3
    end

    subgraph "Access Attempts"
        USER[User]
        ROOT[Root Account]
        ADMIN[Admin with Bypass Permission]
    end

    USER -.Delete V1.-> V1
    ROOT -.Delete V1.-> V1
    ADMIN -.Delete V2.-> V2
    USER -.Delete V3.-> V3

    V1 -.❌ Access Denied<br/>Compliance Mode.-> USER
    V1 -.❌ Access Denied<br/>Even Root Cannot Delete.-> ROOT
    V2 -.✅ Allowed<br/>Has Bypass Permission.-> ADMIN
    V3 -.❌ Access Denied<br/>Legal Hold Active.-> USER

    style V1 fill:#ffebee
    style V2 fill:#fff3e0
    style V3 fill:#f3e5f5
    style BUCKET fill:#e1f5fe

See: diagrams/06_domain5_s3_object_lock.mmd

Diagram Explanation (Detailed):
The S3 Object Lock diagram shows how different retention modes protect object versions. The S3 bucket (blue) has Object Lock and Versioning enabled. Three object versions demonstrate different protection levels. Version 1 (red) is in Compliance mode with retention until 2025-12-31 - absolutely no one, not even the root account, can delete or modify it until that date. When a regular user or even the root account attempts to delete it, they receive "Access Denied" errors. Version 2 (orange) is in Governance mode with retention until 2024-06-30 - regular users cannot delete it, but an administrator with the s3:BypassGovernanceRetention permission can override the protection if needed (for example, to correct a mistake). Version 3 (purple) has a legal hold active - it's protected indefinitely regardless of retention period until the legal hold is explicitly removed. This is used during litigation or investigations. All deletion attempts and Object Lock operations are logged in CloudTrail for audit purposes. This architecture provides flexible data protection: Compliance mode for regulatory requirements, Governance mode for internal policies with override capability, and Legal holds for litigation.

Detailed Example 1: Financial Records Compliance with S3 Object Lock
Your financial services company must retain trading records for 7 years per SEC 17a-4 regulations. You create an S3 bucket named "trading-records" with Object Lock enabled in Compliance mode. You configure a default retention period of 7 years (2,555 days). When traders upload transaction records, S3 automatically applies the 7-year retention period in Compliance mode. Once uploaded, these records cannot be deleted or modified by anyone - not traders, not administrators, not even the AWS root account - for 7 years. If a trader accidentally uploads the wrong file and tries to delete it, they receive an "Access Denied" error. The only option is to upload a new version with the correct data; the incorrect version remains protected for 7 years. After 7 years, the retention period expires and the objects can be deleted. You use S3 Lifecycle policies to automatically delete objects 7 years and 1 day after creation. All access attempts and Object Lock operations are logged in CloudTrail, providing an audit trail for regulatory examiners. This configuration ensures compliance with SEC regulations requiring immutable storage.

Detailed Example 2: Ransomware Protection with S3 Versioning and MFA Delete
Your company stores critical backups in S3 and wants protection against ransomware that might delete or encrypt backups. You enable S3 Versioning on the backup bucket to retain all versions of objects. You enable MFA Delete, which requires multi-factor authentication to permanently delete object versions or disable versioning. You configure bucket policies to deny deletion requests that don't include MFA authentication. Now, if ransomware compromises an IAM user's credentials and attempts to delete backups, the deletion request is denied because it lacks MFA authentication. Even if the ransomware uploads encrypted versions of files (ransomware attack), the original unencrypted versions are preserved due to versioning. To recover, you simply restore the previous versions of objects. For additional protection, you enable Object Lock in Governance mode with a 30-day retention period on backup objects. This prevents even privileged users from accidentally deleting recent backups. Only users with explicit s3:BypassGovernanceRetention permission and MFA can delete backups within the 30-day window. This multi-layered approach (versioning + MFA Delete + Object Lock) provides strong protection against ransomware and accidental deletions.

Detailed Example 3: Legal Hold for Litigation
Your company is involved in litigation and must preserve all emails and documents related to a specific project. You have an S3 bucket containing project documents. You use S3 Batch Operations to place a legal hold on all objects with the tag "Project=LitigationCase". The legal hold prevents deletion of these objects indefinitely, regardless of any retention periods. Even if objects have expired retention periods or no retention at all, the legal hold keeps them protected. During the litigation, new documents are added to the bucket and automatically tagged. A Lambda function triggered by S3 events automatically places legal holds on newly uploaded objects with the litigation tag. When the litigation concludes, your legal team reviews the case and determines which documents can be released. You use S3 Batch Operations again to remove legal holds from objects that are no longer needed. Objects without legal holds can then be deleted normally. Throughout the process, all legal hold operations are logged in CloudTrail, providing a complete audit trail of what was preserved, when, and by whom. This ensures compliance with legal discovery requirements and prevents spoliation of evidence.

Must Know (Critical Facts):

  • Object Lock requires versioning - cannot be enabled without versioning
  • Object Lock can only be enabled at bucket creation - cannot enable on existing buckets
  • Compliance mode: No one can delete objects during retention, not even root account
  • Governance mode: Users with bypass permission can delete objects during retention
  • Legal holds: Independent of retention periods, prevent deletion indefinitely until removed
  • MFA Delete: Requires MFA to permanently delete versions or disable versioning
  • S3 Block Public Access: Prevents accidental public exposure at bucket and account levels

When to use (Comprehensive):

  • ✅ Use Compliance mode when: Regulatory requirements mandate immutable storage (SEC, FINRA, HIPAA)
  • ✅ Use Governance mode when: Internal policies require retention but need override capability
  • ✅ Use Legal holds when: Litigation or investigation requires indefinite preservation
  • ✅ Use MFA Delete when: Protecting critical data from accidental or malicious deletion
  • ✅ Use S3 Block Public Access when: Preventing any possibility of public data exposure
  • ❌ Don't use Object Lock when: You need to frequently modify or delete objects - it's for immutable storage
  • ❌ Don't use Compliance mode when: You might need to delete objects early - use Governance mode instead

Limitations & Constraints:

  • Object Lock cannot be enabled on existing buckets - must create new bucket
  • Compliance mode retention cannot be shortened - can only extend
  • Legal holds can only be removed by users with s3:PutObjectLegalHold permission
  • MFA Delete requires bucket owner's root account credentials to enable/disable
  • Object Lock works at version level - each version has its own retention settings

💡 Tips for Understanding:

  • Think of Compliance mode as "locked safe" - no one can open until timer expires
  • Think of Governance mode as "locked safe with master key" - authorized users can override
  • Legal holds = indefinite protection, retention periods = time-based protection
  • Remember: Object Lock protects versions, not objects - versioning is required

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Trying to enable Object Lock on existing bucket
    • Why it's wrong: Object Lock requires special bucket configuration at creation time
    • Correct understanding: Object Lock can only be enabled when creating a new bucket. To protect existing data, create new bucket with Object Lock and copy objects
  • Mistake 2: Thinking Governance mode provides same protection as Compliance mode
    • Why it's wrong: Governance mode can be bypassed by users with special permissions
    • Correct understanding: Governance mode is for internal policies with override capability. For regulatory compliance requiring absolute immutability, use Compliance mode
  • Mistake 3: Assuming Object Lock automatically deletes objects after retention expires
    • Why it's wrong: Object Lock only prevents deletion during retention, doesn't cause deletion
    • Correct understanding: After retention expires, objects remain in bucket until explicitly deleted. Use S3 Lifecycle policies to automatically delete objects after retention expiration

🔗 Connections to Other Topics:

  • Relates to S3 Versioning because: Object Lock requires versioning to protect object versions
  • Builds on IAM by: Using IAM policies to control who can bypass Governance mode or remove legal holds
  • Often used with CloudTrail to: Log all Object Lock operations for compliance auditing
  • Integrates with S3 Lifecycle to: Automatically delete objects after retention periods expire

Troubleshooting Common Issues:

  • Issue 1: Cannot enable Object Lock on existing bucket
    • Solution: Create new bucket with Object Lock enabled, then copy objects from old bucket to new bucket using S3 Batch Operations or AWS DataSync
  • Issue 2: Cannot delete object even though retention period expired
    • Solution: Check if legal hold is active on the object. Remove legal hold before attempting deletion
  • Issue 3: MFA Delete not working
    • Solution: MFA Delete must be enabled by bucket owner's root account credentials (not IAM user). Use root account with MFA device to enable feature

Section 3: Protecting Credentials, Secrets, and Cryptographic Keys

Introduction

The problem: Applications need access to sensitive information like database passwords, API keys, and encryption keys. Hardcoding these in application code or configuration files creates security risks - credentials can be exposed in version control, logs, or compromised systems. Manual rotation is error-prone and often neglected.

The solution: AWS provides Secrets Manager for automatic secret rotation and centralized secret management, Systems Manager Parameter Store for configuration and secrets storage, and KMS for cryptographic key management. These services provide secure storage, automatic rotation, fine-grained access control, and audit trails.

Why it's tested: The exam tests your ability to choose the right service for different use cases, implement automatic secret rotation, secure secret access, and manage encryption keys. You must understand the differences between Secrets Manager and Parameter Store, and when to use each.

Core Concepts

AWS Secrets Manager for Secret Rotation

What it is: AWS Secrets Manager is a fully managed service for storing, retrieving, and automatically rotating secrets like database credentials, API keys, and OAuth tokens. It integrates with RDS, Redshift, DocumentDB, and other AWS services for automatic credential rotation.

Why it exists: Manual secret rotation is time-consuming, error-prone, and often skipped, leading to security risks. Hardcoded credentials in code are difficult to update and can be exposed in version control. Secrets Manager automates rotation, provides centralized management, and ensures applications always use current credentials.

Real-world analogy: Secrets Manager is like an automated key management system in a large building. Instead of manually changing locks and distributing new keys to everyone (manual rotation), the system automatically changes locks on a schedule and updates everyone's key cards electronically. No one needs to manually distribute keys or worry about old keys still working.

How Secrets Manager rotation works (Detailed step-by-step):

  1. Secret Creation: You create a secret in Secrets Manager, storing credentials as key-value pairs (username, password, host, port). You specify the secret type (RDS, Redshift, DocumentDB, or generic).

  2. Rotation Configuration: You enable automatic rotation and specify the rotation schedule (30, 60, 90 days, or custom). For RDS databases, Secrets Manager automatically creates a Lambda function to handle rotation.

  3. Rotation Trigger: When the rotation schedule triggers, Secrets Manager invokes the rotation Lambda function. The function receives the secret ARN and a rotation token (unique identifier for this rotation).

  4. Create New Secret (createSecret): The Lambda function generates a new password and creates a new user in the database (or updates the existing user's password). The new credentials are stored in Secrets Manager with a "AWSPENDING" label.

  5. Set New Secret (setSecret): The Lambda function updates the database to use the new credentials. For RDS, it creates a new user or changes the existing user's password.

  6. Test New Secret (testSecret): The Lambda function tests the new credentials by connecting to the database. If the connection fails, the rotation is aborted and the old credentials remain active.

  7. Finish Rotation (finishSecret): If testing succeeds, Secrets Manager moves the "AWSCURRENT" label from the old version to the new version. Applications retrieving the secret now get the new credentials. The old version is labeled "AWSPREVIOUS" and retained for recovery.

  8. Application Retrieval: Applications call GetSecretValue API to retrieve the current secret. Secrets Manager returns the version labeled "AWSCURRENT". Applications don't need to know about rotation - they always get current credentials.

📊 Secrets Manager Rotation Diagram:

sequenceDiagram
    participant SM as Secrets Manager
    participant Lambda as Rotation Lambda
    participant DB as RDS Database
    participant App as Application

    Note over SM,DB: Rotation Triggered (30-day schedule)
    SM->>Lambda: 1. Invoke rotation function
    Lambda->>Lambda: 2. Generate new password
    Lambda->>SM: 3. Store new secret (AWSPENDING)
    Lambda->>DB: 4. Create new user or update password
    Lambda->>DB: 5. Test connection with new credentials
    DB-->>Lambda: 6. Connection successful
    Lambda->>SM: 7. Mark new version as AWSCURRENT
    SM->>SM: 8. Mark old version as AWSPREVIOUS

    Note over SM,App: Application retrieves secret
    App->>SM: 9. GetSecretValue()
    SM-->>App: 10. Return AWSCURRENT version (new credentials)
    App->>DB: 11. Connect with new credentials

See: diagrams/06_domain5_secrets_manager_rotation.mmd

Diagram Explanation (Detailed):
The Secrets Manager rotation diagram shows the complete automatic rotation process. When the rotation schedule triggers (every 30 days in this example), Secrets Manager invokes the rotation Lambda function. The Lambda function generates a new random password and stores it in Secrets Manager with the "AWSPENDING" label - this is a staging version not yet active. The function then connects to the RDS database and either creates a new database user with the new password or updates the existing user's password. It tests the new credentials by attempting a database connection. If the connection succeeds, the Lambda function tells Secrets Manager to mark the new version as "AWSCURRENT" (active) and the old version as "AWSPREVIOUS" (retained for recovery). When applications call GetSecretValue, they automatically receive the AWSCURRENT version with the new credentials. Applications don't need to be aware of rotation - they simply retrieve the secret before each database connection. The old credentials (AWSPREVIOUS) are retained for a period to allow in-flight requests to complete. This entire process happens automatically without application downtime or manual intervention.

Detailed Example 1: RDS MySQL Automatic Rotation
Your application uses an RDS MySQL database and you want to rotate credentials every 30 days. You create a secret in Secrets Manager, selecting "Credentials for RDS database" as the secret type. You provide the database endpoint, username, and password. You enable automatic rotation with a 30-day schedule. Secrets Manager automatically creates a Lambda function in your account with the necessary code to rotate RDS MySQL credentials. The Lambda function is granted permissions to access the secret and connect to the database. Every 30 days, Secrets Manager triggers the rotation. The Lambda function generates a new password, connects to MySQL as the master user, and creates a new user with the new password (or updates the existing user's password). It tests the new credentials, and if successful, marks them as current. Your application code retrieves the secret using the AWS SDK: secretsmanager.get_secret_value(SecretId='prod/mysql/app'). The application parses the JSON response to get the current username, password, and host. It creates a database connection using these credentials. Because the application retrieves the secret on each connection (or caches it for a short period), it automatically uses the new credentials after rotation without code changes or restarts.

Detailed Example 2: API Key Rotation with Custom Lambda
Your application uses a third-party API that requires an API key. The API provider requires key rotation every 90 days. You store the API key in Secrets Manager and create a custom Lambda function for rotation. The Lambda function implements the four required methods: createSecret (generates new key via API provider's API), setSecret (activates new key with provider), testSecret (makes test API call), and finishSecret (marks new key as current). You configure Secrets Manager to invoke this Lambda function every 90 days. When rotation triggers, the Lambda function calls the API provider's key management API to generate a new key. It stores the new key in Secrets Manager with AWSPENDING label. It activates the new key with the provider (some providers allow multiple active keys during transition). It makes a test API call using the new key. If successful, it marks the new key as AWSCURRENT. Your application retrieves the API key from Secrets Manager before making API calls. After rotation, it automatically uses the new key. The old key (AWSPREVIOUS) remains valid for 24 hours to allow in-flight requests to complete, then the Lambda function deactivates it with the provider.

Detailed Example 3: Cross-Account Secret Access
Your organization has a shared services account that hosts an RDS database used by applications in multiple AWS accounts. You store the database credentials in Secrets Manager in the shared services account. You need to grant applications in other accounts access to the secret. You create a resource-based policy on the secret that allows specific IAM roles from other accounts to call GetSecretValue. In the application account, you create an IAM role with permissions to access the secret in the shared services account. Your application assumes this role and retrieves the secret: secretsmanager.get_secret_value(SecretId='arn:aws:secretsmanager:us-east-1:123456789012:secret:shared/database'). The cross-account access is logged in CloudTrail in both accounts. When the secret rotates in the shared services account, all applications in all accounts automatically receive the new credentials on their next retrieval. This centralized secret management reduces duplication and ensures consistent credential rotation across all applications.

Must Know (Critical Facts):

  • Secrets Manager automatically rotates secrets for RDS, Redshift, DocumentDB - Lambda function created automatically
  • Rotation uses four-step process: createSecret, setSecret, testSecret, finishSecret
  • Applications should retrieve secrets on each use or cache for short periods (not hardcode)
  • Secrets Manager charges $0.40 per secret per month + $0.05 per 10,000 API calls
  • Secrets can be shared cross-account using resource-based policies
  • Secrets Manager integrates with VPC endpoints for private access without internet
  • Secret versions are labeled: AWSCURRENT (active), AWSPENDING (rotating), AWSPREVIOUS (old)

When to use (Comprehensive):

  • ✅ Use Secrets Manager when: You need automatic secret rotation for databases or APIs
  • ✅ Use Secrets Manager when: Storing database credentials, API keys, OAuth tokens
  • ✅ Use Secrets Manager when: You need built-in rotation for RDS, Redshift, DocumentDB
  • ✅ Use Secrets Manager when: You need cross-region secret replication
  • ✅ Use Secrets Manager when: Compliance requires regular credential rotation
  • ❌ Don't use Secrets Manager when: You need to store thousands of parameters - use Parameter Store (cheaper)
  • ❌ Don't use Secrets Manager when: You don't need rotation and want to minimize costs - use Parameter Store

Limitations & Constraints:

  • Secret size limit: 65,536 bytes (64 KB)
  • Rotation Lambda function must complete within 15 minutes (Lambda timeout)
  • Minimum rotation interval: 1 day (cannot rotate more frequently)
  • Secret name must be unique within account and region
  • Maximum 50 versions per secret (old versions automatically deleted)

💡 Tips for Understanding:

  • Think of Secrets Manager as "automatic password changer" - sets schedule, changes passwords, updates applications
  • Remember: AWSCURRENT = active version, AWSPENDING = rotating version, AWSPREVIOUS = old version
  • Rotation doesn't cause downtime - old credentials remain valid during rotation
  • Applications should retrieve secrets dynamically, not cache indefinitely

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Hardcoding secret ARN in application code
    • Why it's wrong: Makes it difficult to change secrets or move between environments
    • Correct understanding: Use environment variables or parameter store to store secret ARN, allowing easy configuration changes
  • Mistake 2: Caching secrets indefinitely in application memory
    • Why it's wrong: Application won't pick up rotated credentials until restart
    • Correct understanding: Retrieve secrets on each use or cache for short periods (5-10 minutes). Implement retry logic to handle rotation transitions
  • Mistake 3: Thinking rotation causes application downtime
    • Why it's wrong: Rotation is designed to be seamless with zero downtime
    • Correct understanding: During rotation, both old and new credentials are valid briefly. Applications using old credentials continue working while new credentials are tested and activated

🔗 Connections to Other Topics:

  • Relates to Lambda because: Rotation is implemented using Lambda functions
  • Builds on IAM by: Using IAM policies and resource policies to control secret access
  • Often used with RDS to: Automatically rotate database credentials
  • Integrates with VPC Endpoints to: Access secrets privately without internet gateway

Troubleshooting Common Issues:

  • Issue 1: Rotation fails with "Unable to connect to database"
    • Solution: Check Lambda function's VPC configuration. Ensure Lambda is in same VPC as database or has network connectivity. Verify security groups allow Lambda to connect to database
  • Issue 2: Application gets "Access Denied" when retrieving secret
    • Solution: Check IAM policy grants secretsmanager:GetSecretValue permission. For encrypted secrets, also need kms:Decrypt permission on KMS key
  • Issue 3: Rotation succeeds but application still uses old credentials
    • Solution: Application is caching credentials too long. Reduce cache TTL or implement retry logic to handle credential changes

Chapter Summary

What We Covered

  • Data in Transit Protection: TLS/SSL encryption, VPN/IPsec, Session Manager for secure remote access
  • Data at Rest Protection: KMS encryption, envelope encryption, S3/EBS/RDS encryption
  • Data Integrity: S3 Object Lock, versioning, MFA Delete, immutable storage
  • Secret Management: Secrets Manager rotation, Parameter Store, KMS key management

Critical Takeaways

  1. TLS Encryption: Use TLS 1.2+ for all data in transit. ACM provides free certificates for AWS services. SNI allows multiple certificates on same IP.
  2. VPN Connectivity: Site-to-Site VPN provides encrypted connectivity over internet. Two tunnels for high availability. Accelerated VPN uses AWS global network.
  3. Session Manager: Secure shell access without SSH keys or open ports. All communication outbound over HTTPS. Complete audit trails in CloudWatch Logs.
  4. Envelope Encryption: Data encrypted with DEK, DEK encrypted with KMS key. Provides performance and security. Keys never leave KMS.
  5. S3 Object Lock: Compliance mode = immutable (even root can't delete). Governance mode = override capability. Legal holds = indefinite protection.
  6. Secrets Manager: Automatic rotation for RDS, Redshift, DocumentDB. Four-step rotation process. Applications retrieve current version automatically.
  7. KMS Key Management: Customer-managed keys provide audit trails and access control. Automatic rotation creates new key material yearly. Keys are regional.

Self-Assessment Checklist

Test yourself before moving on:

  • I can explain the difference between TLS 1.2 and TLS 1.3
  • I understand how envelope encryption works and why it's used
  • I can describe the difference between Compliance and Governance mode in S3 Object Lock
  • I know when to use Secrets Manager vs Parameter Store
  • I understand how Session Manager provides access without open inbound ports
  • I can explain the four steps of Secrets Manager rotation
  • I know the difference between SSE-S3, SSE-KMS, and SSE-C encryption
  • I understand how VPN provides encrypted connectivity over the internet

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-25 (Data in Transit)
  • Domain 5 Bundle 2: Questions 26-50 (Data at Rest and Secrets)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections: TLS concepts, envelope encryption, S3 Object Lock modes
  • Focus on: When to use each encryption method, secret rotation process, Object Lock retention modes

Quick Reference Card

[One-page summary of chapter - copy to your notes]

Key Services:

  • ACM: Free SSL/TLS certificates for AWS services, automatic renewal
  • VPN: Encrypted connectivity over internet, 1.25 Gbps per tunnel
  • Session Manager: Secure shell access without SSH keys or open ports
  • KMS: Centralized key management, envelope encryption, automatic rotation
  • Secrets Manager: Automatic secret rotation, $0.40/secret/month
  • Parameter Store: Configuration and secrets storage, free tier available
  • S3 Object Lock: Immutable storage, Compliance/Governance modes

Key Concepts:

  • TLS 1.2+: Minimum version for secure connections
  • Envelope Encryption: Data encrypted with DEK, DEK encrypted with KMS key
  • Compliance Mode: Immutable, even root cannot delete
  • Governance Mode: Override capability with special permissions
  • AWSCURRENT: Active secret version
  • AWSPENDING: Rotating secret version
  • AWSPREVIOUS: Old secret version (retained for recovery)

Decision Points:

  • Need audit trails for encryption? → Use SSE-KMS (not SSE-S3)
  • Need automatic secret rotation? → Use Secrets Manager (not Parameter Store)
  • Need immutable storage for compliance? → Use S3 Object Lock Compliance mode
  • Need secure remote access without SSH? → Use Session Manager
  • Need encrypted connectivity to on-premises? → Use Site-to-Site VPN
  • Need to share encrypted data cross-account? → Grant KMS key permissions

Common Exam Traps:

  • ❌ ACM certificates can be exported → FALSE (keys never leave AWS)
  • ❌ Object Lock can be enabled on existing buckets → FALSE (only at creation)
  • ❌ Automatic key rotation re-encrypts existing data → FALSE (only new operations)
  • ❌ Session Manager requires open inbound ports → FALSE (outbound only)
  • ❌ VPN provides dedicated bandwidth → FALSE (depends on internet connection)
  • ❌ Secrets Manager is free → FALSE ($0.40/secret/month + API calls)


Chapter Summary

What We Covered

This chapter covered Domain 5: Data Protection (18% of exam), including:

  • Data in Transit: TLS, VPN, Session Manager, certificate management, secure connectivity
  • Data at Rest: Encryption techniques, KMS, S3 encryption, RDS encryption, EBS encryption
  • Data Lifecycle: S3 Object Lock, Glacier Vault Lock, retention policies, AWS Backup
  • Secrets Management: Secrets Manager, Parameter Store, automatic rotation
  • Key Management: KMS, symmetric/asymmetric keys, key rotation, multi-region keys

Critical Takeaways

  1. TLS 1.2+: Minimum version for secure connections, enforce with policies
  2. KMS: Centralized key management, envelope encryption, automatic rotation
  3. S3 Encryption: SSE-S3 (AWS-managed), SSE-KMS (customer-managed), SSE-C (customer-provided)
  4. S3 Object Lock: Immutable storage, Compliance mode (cannot delete), Governance mode (override with permissions)
  5. Secrets Manager: Automatic secret rotation, RDS integration, $0.40/secret/month
  6. Parameter Store: Configuration and secrets, free tier, SecureString with KMS
  7. Session Manager: Secure remote access without SSH/RDP, no open ports
  8. VPN: Encrypted connectivity to on-premises, IPsec tunnels
  9. Envelope Encryption: Data encrypted with DEK, DEK encrypted with KMS key
  10. Key Rotation: Automatic rotation for KMS keys, manual rotation for imported keys

Self-Assessment Checklist

Test yourself before moving on:

  • I understand TLS concepts and how to enforce TLS 1.2+
  • I know the difference between SSE-S3, SSE-KMS, and SSE-C
  • I can design encryption strategies for data at rest
  • I understand S3 Object Lock and Glacier Vault Lock
  • I know how to use Secrets Manager for automatic rotation
  • I understand KMS key policies and grants
  • I can design secure remote access solutions
  • I know how to implement data lifecycle policies
  • I understand envelope encryption
  • I can troubleshoot encryption issues

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-25 (Encryption focus)
  • Domain 5 Bundle 2: Questions 26-50 (Lifecycle and Secrets focus)
  • Data Encryption Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: KMS key policies, S3 Object Lock, Secrets Manager rotation
  • Focus on: Encryption selection, lifecycle management, key management

Quick Reference Card

Key Services:

  • KMS: Key management, envelope encryption, automatic rotation
  • Secrets Manager: Secret storage, automatic rotation, RDS integration
  • Parameter Store: Configuration and secrets, free tier
  • S3 Object Lock: Immutable storage, compliance and governance modes
  • ACM: Certificate management, automatic renewal
  • Session Manager: Secure remote access, no SSH/RDP

Encryption Options:

  • SSE-S3: AWS-managed keys, free, AES-256
  • SSE-KMS: Customer-managed keys, audit trail, key policies
  • SSE-C: Customer-provided keys, customer manages keys
  • Client-side: Encrypt before upload, full control

Decision Points:

  • Need audit trail for encryption? → SSE-KMS (not SSE-S3)
  • Need automatic secret rotation? → Secrets Manager (not Parameter Store)
  • Need immutable storage? → S3 Object Lock Compliance mode
  • Need secure remote access? → Session Manager (not SSH/RDP)
  • Need encrypted connectivity? → VPN or Direct Connect + MACsec
  • Need to share encrypted data cross-account? → KMS key policy grants

Best Practices:

  1. Encrypt all data at rest (S3, EBS, RDS, DynamoDB)
  2. Use TLS 1.2+ for data in transit
  3. Enable automatic key rotation for KMS keys
  4. Use Secrets Manager for database credentials
  5. Implement S3 Object Lock for compliance
  6. Use Session Manager instead of SSH/RDP
  7. Enable MFA Delete for S3 buckets
  8. Use envelope encryption for large data
  9. Implement data lifecycle policies
  10. Audit encryption with CloudTrail and Config

Chapter 5 Complete

Next Chapter: 07_domain6_governance - Management and Security Governance (14% of exam)


Chapter Summary

What We Covered

This chapter explored Data Protection, covering encryption and lifecycle management:

Data in Transit: Designing controls for confidentiality and integrity of data in transit using TLS, VPN (IPsec), secure remote access (Session Manager, EC2 Instance Connect), TLS certificates with CloudFront and load balancers, and secure connectivity with Direct Connect and VPN gateways.

Data at Rest: Designing controls for confidentiality and integrity of data at rest through encryption technique selection (client-side, server-side, symmetric, asymmetric), resource policies, preventing unauthorized public access, configuring encryption at rest for AWS services, and protecting data integrity with S3 Object Lock and Glacier Vault Lock.

Data Lifecycle: Managing the lifecycle of data at rest with S3 Lifecycle policies, Object Lock, Glacier Vault Lock, automatic lifecycle management for EBS, RDS, AMIs, CloudWatch logs, and AWS Backup schedules and retention.

Secrets Management: Protecting credentials, secrets, and cryptographic keys using Secrets Manager for automatic rotation, Parameter Store for configuration and secrets, KMS for key management (symmetric and asymmetric keys), and importing customer-provided key material.

Critical Takeaways

  1. Encrypt Everything: Encrypt data at rest and in transit by default. Use AWS managed encryption when possible (S3 SSE-S3, EBS default encryption) and KMS customer managed keys when you need control over key policies and rotation.

  2. TLS 1.2 Minimum: Always use TLS 1.2 or higher for data in transit. Disable older protocols (SSL, TLS 1.0, TLS 1.1) that have known vulnerabilities. Use strong cipher suites.

  3. Envelope Encryption: AWS uses envelope encryption for performance. Data is encrypted with a data key, and the data key is encrypted with a KMS key. This allows efficient encryption of large datasets.

  4. Immutability for Compliance: Use S3 Object Lock (compliance mode) or Glacier Vault Lock to make data immutable for regulatory compliance. Once locked, even the root account cannot delete or modify the data.

  5. Secrets Rotation: Rotate secrets regularly using Secrets Manager's automatic rotation feature. Never hardcode secrets in code or configuration files. Use IAM roles to retrieve secrets at runtime.

  6. Key Policies are Critical: KMS key policies control who can use and manage keys. Always follow least privilege. Use key policies to enforce encryption (deny unencrypted uploads to S3).

  7. Lifecycle Automation: Automate data lifecycle management to reduce costs and ensure compliance. Use S3 Lifecycle policies to transition data to cheaper storage classes and delete old data. Use Data Lifecycle Manager for EBS snapshots and AMIs.

  8. Session Manager Over SSH: Use Systems Manager Session Manager instead of SSH/RDP for secure remote access. Session Manager doesn't require open inbound ports, provides session logging, and integrates with IAM for authentication.

Self-Assessment Checklist

Test yourself before moving on:

  • I understand TLS concepts and how to configure TLS for AWS services
  • I know how to implement VPN connectivity with IPsec
  • I can configure Session Manager for secure remote access
  • I understand how to use TLS certificates with CloudFront and load balancers
  • I know how to secure Direct Connect with VPN or MACsec
  • I understand the difference between client-side and server-side encryption
  • I know when to use symmetric vs asymmetric encryption
  • I can write resource policies to restrict access to encrypted data
  • I understand how to prevent unauthorized public access (S3 Block Public Access, prevent public snapshots)
  • I can configure encryption at rest for S3, EBS, RDS, DynamoDB, EFS, and SQS
  • I know how to use S3 Object Lock and Glacier Vault Lock for data integrity
  • I understand envelope encryption and how KMS works
  • I can design S3 Lifecycle policies for data retention and archival
  • I know how to use Data Lifecycle Manager for EBS snapshots and AMIs
  • I can configure AWS Backup for automated backup and retention
  • I understand Secrets Manager and automatic secret rotation
  • I know the difference between Secrets Manager and Parameter Store
  • I can create and manage KMS keys (symmetric and asymmetric)
  • I understand KMS key policies and how to grant access to keys
  • I know how to import customer-provided key material into KMS

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-25 (Data in Transit and Data at Rest)
  • Domain 5 Bundle 2: Questions 26-50 (Data Lifecycle and Secrets Management)
  • Data Encryption Bundle: All 50 questions (Encryption-specific scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review TLS configuration for CloudFront and load balancers
  • Practice designing encryption strategies for different AWS services
  • Study S3 Object Lock modes (compliance vs governance)
  • Focus on Secrets Manager rotation and KMS key policies
  • Review envelope encryption and how KMS encrypts data

Quick Reference Card

Data in Transit Services:

  • TLS/SSL: Encryption protocol for HTTPS (use TLS 1.2+)
  • VPN: Site-to-Site VPN with IPsec encryption
  • Session Manager: Secure remote access without SSH/RDP
  • ACM: AWS Certificate Manager for TLS certificates
  • Direct Connect: Dedicated network connection (add VPN or MACsec for encryption)

Data at Rest Services:

  • S3 Encryption: SSE-S3 (AWS managed), SSE-KMS (customer managed), SSE-C (customer provided)
  • EBS Encryption: Default encryption with KMS
  • RDS Encryption: Encryption at rest with KMS (must enable at creation)
  • DynamoDB Encryption: Encryption at rest with KMS (enabled by default)
  • EFS Encryption: Encryption at rest with KMS
  • S3 Object Lock: Immutable storage (compliance or governance mode)
  • Glacier Vault Lock: Immutable archival storage

Secrets Management Services:

  • Secrets Manager: Automatic secret rotation, RDS integration
  • Parameter Store: Configuration and secrets storage (SecureString with KMS)
  • KMS: Key management service (symmetric and asymmetric keys)

Encryption Types:

  • Symmetric: Same key for encryption and decryption (AES-256, faster)
  • Asymmetric: Public key for encryption, private key for decryption (RSA, slower)
  • Client-Side: Data encrypted before sending to AWS
  • Server-Side: AWS encrypts data after receiving it
  • Envelope Encryption: Data encrypted with data key, data key encrypted with KMS key

S3 Object Lock Modes:

  • Compliance Mode: Cannot be deleted or modified by anyone (including root)
  • Governance Mode: Can be deleted/modified with special permissions
  • Legal Hold: Indefinite retention until explicitly removed

Decision Points:

  • Data in transit → TLS 1.2+ for HTTPS, IPsec for VPN
  • Remote access → Session Manager (no SSH/RDP ports needed)
  • S3 encryption → SSE-S3 (simple), SSE-KMS (control), SSE-C (customer keys)
  • RDS encryption → Enable at creation (cannot enable later without migration)
  • Immutable storage → S3 Object Lock (compliance mode) or Glacier Vault Lock
  • Secret rotation → Secrets Manager (automatic) or Parameter Store (manual)
  • Key management → KMS customer managed keys (control) or AWS managed keys (simple)
  • Direct Connect encryption → VPN over Direct Connect (IPsec) or MACsec (Layer 2)

Exam Tips:

  • Know that RDS encryption must be enabled at creation time (cannot enable later)
  • Understand the difference between S3 Object Lock compliance mode (immutable) and governance mode (deletable with permissions)
  • Remember that envelope encryption is used for performance (data key encrypts data, KMS key encrypts data key)
  • Session Manager is preferred over SSH/RDP (no open ports, session logging, IAM authentication)
  • Secrets Manager provides automatic rotation, Parameter Store does not
  • KMS key policies control access to keys (separate from IAM policies)
  • S3 Block Public Access should be enabled at account and bucket level
  • MACsec provides Layer 2 encryption for Direct Connect (faster than VPN)


Chapter Summary

What We Covered

This chapter explored AWS data protection capabilities across four critical areas:

Confidentiality and Integrity for Data in Transit

  • TLS concepts and implementation for encrypted communications
  • VPN concepts (IPsec) for secure network connectivity
  • Secure remote access using Session Manager and EC2 Instance Connect
  • TLS certificates with CloudFront, load balancers, and other network services
  • Secure connectivity between AWS and on-premises (Direct Connect, VPN gateways, MACsec)

Confidentiality and Integrity for Data at Rest

  • Encryption technique selection (client-side, server-side, symmetric, asymmetric)
  • Resource policies to restrict access to authorized users
  • Preventing unauthorized public access (S3 Block Public Access, public snapshot prevention)
  • Configuring encryption at rest for AWS services (S3, RDS, DynamoDB, EBS, EFS, SQS)
  • Data integrity protection using S3 Object Lock, KMS key policies, Glacier Vault Lock

Lifecycle Management for Data at Rest

  • S3 Lifecycle mechanisms (Object Lock, Glacier Vault Lock, Lifecycle policies)
  • Automatic lifecycle management for AWS resources (EBS snapshots, RDS snapshots, AMIs, CloudWatch logs)
  • AWS Backup schedules and retention policies across services

Protecting Credentials, Secrets, and Cryptographic Keys

  • Secrets Manager for secret management and automatic rotation
  • Systems Manager Parameter Store for configuration and secrets
  • KMS key management (symmetric and asymmetric keys, key rotation, multi-region keys)
  • Customer-provided key material and custom key stores with CloudHSM

Critical Takeaways

  1. Encrypt everything: Enable encryption at rest for all data stores (S3, RDS, DynamoDB, EBS, EFS)
  2. TLS 1.2 minimum: Enforce TLS 1.2 or higher for all data in transit
  3. KMS for encryption keys: Use AWS KMS for centralized key management with automatic rotation
  4. S3 Block Public Access: Enable at account and bucket level to prevent accidental public exposure
  5. S3 Object Lock for compliance: Use compliance mode for immutable data retention (cannot be deleted even by root)
  6. Secrets Manager for rotation: Use Secrets Manager for automatic secret rotation (RDS, Redshift, DocumentDB)
  7. Session Manager for remote access: Replace SSH/RDP with Session Manager for secure, audited remote access
  8. MACsec for Direct Connect: Use MACsec for layer 2 encryption on Direct Connect connections
  9. Envelope encryption: KMS uses envelope encryption (data key encrypts data, KMS key encrypts data key)
  10. CloudHSM for compliance: Use CloudHSM custom key store when FIPS 140-2 Level 3 compliance is required
  11. Glacier Vault Lock: Use for long-term archival with write-once-read-many (WORM) compliance
  12. AWS Backup for centralized backup: Use AWS Backup for centralized backup management across services

Self-Assessment Checklist

Test yourself before moving on:

Data in Transit:

  • I understand TLS concepts and how to enforce TLS 1.2+ for AWS services
  • I can design VPN solutions using IPsec for secure connectivity
  • I know how to use Session Manager for secure remote access without SSH/RDP
  • I can configure TLS certificates with ACM for CloudFront and load balancers
  • I understand Direct Connect encryption options (VPN over DX, MACsec)

Data at Rest:

  • I can choose appropriate encryption techniques (client-side vs server-side, symmetric vs asymmetric)
  • I understand how to configure encryption at rest for all major AWS services
  • I know how to use resource policies to restrict access to encrypted data
  • I can prevent unauthorized public access using S3 Block Public Access and other controls
  • I understand data integrity protection using S3 Object Lock and Glacier Vault Lock

Lifecycle Management:

  • I can design S3 Lifecycle policies for data retention and archival
  • I understand S3 Object Lock modes (compliance vs governance)
  • I know how to use AWS Backup for centralized backup management
  • I can configure automatic lifecycle management for EBS snapshots, AMIs, and logs
  • I understand retention requirements and how to implement them

Secrets and Keys:

  • I can use Secrets Manager for secret storage and automatic rotation
  • I understand when to use Secrets Manager vs Parameter Store
  • I know how to manage KMS keys (creation, rotation, policies, grants)
  • I can design key hierarchies and understand envelope encryption
  • I understand when to use CloudHSM custom key stores

Advanced Concepts:

  • I can design cross-account KMS key access
  • I understand KMS multi-region keys for disaster recovery
  • I know how to import customer-provided key material
  • I can configure AWS Backup Vault Lock for immutable backups
  • I understand the differences between KMS, CloudHSM, and ACM

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-25 (Data in Transit and at Rest)
  • Domain 5 Bundle 2: Questions 26-50 (Lifecycle and Secrets Management)
  • Data Encryption Bundle: Questions 1-50 (Encryption-specific scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review KMS key policies and how they interact with IAM policies
  • Practice designing S3 Lifecycle policies with Object Lock
  • Focus on understanding Secrets Manager rotation mechanisms
  • Review encryption at rest configuration for each AWS service

Quick Reference Card

Key Services:

  • KMS: Key Management Service for encryption key management
  • Secrets Manager: Secret storage with automatic rotation
  • Parameter Store: Configuration and secret storage (part of Systems Manager)
  • ACM: AWS Certificate Manager for TLS certificates
  • CloudHSM: Hardware security module for FIPS 140-2 Level 3 compliance
  • S3 Object Lock: Immutable object storage (WORM)
  • Glacier Vault Lock: Immutable archive storage
  • AWS Backup: Centralized backup management across services

Key Concepts:

  • Encryption at Rest: Data encrypted when stored on disk
  • Encryption in Transit: Data encrypted during transmission (TLS/SSL)
  • Envelope Encryption: Data key encrypts data, KMS key encrypts data key
  • Client-Side Encryption: Data encrypted before sending to AWS
  • Server-Side Encryption: AWS encrypts data after receiving it
  • S3-SSE: S3-managed keys (SSE-S3), KMS keys (SSE-KMS), customer keys (SSE-C)
  • Object Lock: Prevents object deletion/modification for retention period
  • Vault Lock: Prevents policy changes on Glacier vault (compliance)

Encryption Options by Service:

  • S3: SSE-S3, SSE-KMS, SSE-C, client-side encryption
  • EBS: KMS encryption (enabled by default for new volumes)
  • RDS: KMS encryption (must enable at creation, cannot enable later)
  • DynamoDB: KMS encryption (enabled by default)
  • EFS: KMS encryption (can enable at creation or later)
  • SQS: KMS encryption (optional)

Decision Points:

  • Data in transit → TLS 1.2+ (enforce with bucket policies, ALB policies)
  • Remote access → Session Manager (not SSH/RDP with bastion)
  • Direct Connect encryption → VPN over DX (layer 3) or MACsec (layer 2)
  • S3 encryption → SSE-KMS (for key rotation and audit) or SSE-S3 (simpler)
  • RDS encryption → Enable at creation (cannot enable later without migration)
  • Secret storage → Secrets Manager (with rotation) or Parameter Store (simpler)
  • Secret rotation → Secrets Manager (automatic) or Lambda (custom)
  • Compliance retention → S3 Object Lock compliance mode or Glacier Vault Lock
  • Key management → KMS (most cases) or CloudHSM (FIPS 140-2 Level 3)
  • Cross-region encryption → KMS multi-region keys
  • Backup management → AWS Backup (centralized) or service-native (simpler)

S3 Object Lock Modes:

  • Compliance: Cannot be deleted by anyone, including root (for regulatory compliance)
  • Governance: Can be deleted by users with special permissions (for operational flexibility)

Secrets Manager vs Parameter Store:

  • Secrets Manager: Automatic rotation, RDS integration, versioning, higher cost
  • Parameter Store: No automatic rotation, simpler, lower cost, hierarchies

  • Backup management → AWS Backup (centralized) or service-native (simpler)

Chapter Summary

What We Covered

This chapter covered Data Protection, accounting for 18% of the SCS-C02 exam. We explored four major task areas:

Task 5.1: Confidentiality and Integrity for Data in Transit

  • Understanding TLS concepts and implementing TLS for AWS services
  • Configuring VPN concepts (IPsec) for secure connectivity
  • Using secure remote access methods (Session Manager, EC2 Instance Connect)
  • Managing TLS certificates with ACM for CloudFront, load balancers, and other services
  • Designing secure connectivity between AWS and on-premises networks (Direct Connect, VPN)

Task 5.2: Confidentiality and Integrity for Data at Rest

  • Selecting encryption techniques (client-side, server-side, symmetric, asymmetric)
  • Designing resource policies to restrict access to authorized users
  • Preventing unauthorized public access (S3 Block Public Access, preventing public snapshots)
  • Configuring encryption at rest for AWS services (S3, RDS, DynamoDB, EBS, EFS, SQS)
  • Protecting data integrity using S3 Object Lock, KMS key policies, Glacier Vault Lock, and Backup Vault Lock

Task 5.3: Managing Lifecycle of Data at Rest

  • Designing S3 Lifecycle mechanisms for data retention (Object Lock, Glacier Vault Lock, Lifecycle policies)
  • Implementing automatic lifecycle management for AWS services (S3, EBS, RDS, AMIs, CloudWatch logs)
  • Establishing schedules and retention for AWS Backup across AWS services

Task 5.4: Protecting Credentials, Secrets, and Cryptographic Keys

  • Managing and rotating secrets using Secrets Manager
  • Using Systems Manager Parameter Store for configuration data and secrets
  • Managing symmetric and asymmetric KMS keys
  • Importing and removing customer-provided key material

Critical Takeaways

  1. Encryption in Transit is Mandatory: Always use TLS 1.2 or higher for data in transit. Enforce HTTPS using bucket policies, ALB listener rules, and API Gateway settings.

  2. Session Manager Replaces SSH/RDP: Never use SSH or RDP with bastion hosts. Use Session Manager for secure, audited remote access without opening ports or managing keys.

  3. KMS is the Default for Encryption: Use AWS KMS for encryption at rest for most services. Only use CloudHSM when you need FIPS 140-2 Level 3 compliance or full control over HSMs.

  4. S3 Object Lock for Compliance: Use S3 Object Lock in compliance mode for immutable data retention. Once enabled, even the root account cannot delete objects until the retention period expires.

  5. Secrets Manager for Automatic Rotation: Use Secrets Manager (not Parameter Store) when you need automatic secret rotation. Secrets Manager integrates with RDS, Redshift, and DocumentDB for automatic rotation.

  6. Envelope Encryption for Performance: KMS uses envelope encryption - data is encrypted with a data key, and the data key is encrypted with a KMS key. This improves performance for large datasets.

  7. Multi-Region Keys for DR: Use KMS multi-region keys when you need to encrypt data in one region and decrypt in another (disaster recovery, global applications).

  8. Backup Vault Lock for Immutability: Use AWS Backup Vault Lock to prevent deletion of backups, even by administrators. This protects against ransomware and insider threats.

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Data in Transit:

  • Explain how TLS handshake works and the role of certificates
  • Configure ALB to enforce HTTPS and redirect HTTP to HTTPS
  • Set up Session Manager for secure remote access to EC2 instances
  • Design a VPN over Direct Connect for encrypted on-premises connectivity
  • Implement MACsec for layer 2 encryption on Direct Connect

Data at Rest:

  • Choose between SSE-S3, SSE-KMS, and SSE-C for S3 encryption
  • Enable encryption at rest for RDS (must be done at creation)
  • Configure S3 Block Public Access at account and bucket levels
  • Implement S3 Object Lock in compliance mode for immutable retention
  • Design KMS key policies to restrict key usage to authorized users

Data Lifecycle:

  • Create S3 Lifecycle policies to transition objects through storage classes
  • Configure Glacier Vault Lock for compliance retention
  • Set up AWS Backup plans with retention policies
  • Implement Data Lifecycle Manager for automated EBS snapshot management

Secrets and Keys:

  • Configure Secrets Manager for automatic RDS password rotation
  • Use Parameter Store SecureString for encrypted configuration data
  • Create and manage KMS customer managed keys
  • Implement KMS key rotation (automatic annual rotation)
  • Import customer-provided key material into KMS

Decision-Making:

  • Choose between Secrets Manager and Parameter Store for different scenarios
  • Determine when to use KMS vs. CloudHSM
  • Select between S3 Object Lock and Glacier Vault Lock for compliance
  • Decide when to use multi-region KMS keys

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-45 (focus on encryption in transit and at rest)
  • Domain 5 Bundle 2: Questions 46-90 (focus on data lifecycle and secrets management)
  • Data Encryption Bundle: Questions covering KMS, Secrets Manager, Parameter Store, encryption at rest/transit
  • Full Practice Test 1: Domain 5 questions (9 questions, 18% of exam)

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • KMS Key Management (if you struggled with encryption key questions)
    • S3 Object Lock vs. Glacier Vault Lock (if you struggled with compliance retention questions)
    • Secrets Manager Rotation (if you struggled with automatic rotation questions)
    • TLS Configuration (if you struggled with data in transit questions)
  • Focus on:
    • Understanding the differences between SSE-S3, SSE-KMS, and SSE-C
    • Memorizing which services support encryption at rest and how to enable it
    • Practicing KMS key policy creation and understanding key policy evaluation
    • Understanding when to use Secrets Manager vs. Parameter Store

Quick Reference Card

Key Services:

  • KMS: Key Management Service for encryption keys (symmetric and asymmetric)
  • Secrets Manager: Automatic secret rotation for databases and applications
  • Parameter Store: Configuration data and secrets storage (part of Systems Manager)
  • ACM: AWS Certificate Manager for TLS certificates
  • CloudHSM: Hardware Security Module for FIPS 140-2 Level 3 compliance
  • S3 Object Lock: Immutable object storage with WORM (Write Once Read Many)
  • Glacier Vault Lock: Immutable archive storage with compliance retention
  • AWS Backup: Centralized backup management across AWS services

Key Concepts:

  • Envelope Encryption: Data encrypted with data key, data key encrypted with KMS key
  • TLS: Transport Layer Security for encrypted data in transit (TLS 1.2+)
  • MACsec: Media Access Control Security for layer 2 encryption on Direct Connect
  • SSE-S3: Server-side encryption with S3-managed keys
  • SSE-KMS: Server-side encryption with KMS-managed keys (audit trail, key rotation)
  • SSE-C: Server-side encryption with customer-provided keys
  • Compliance Mode: S3 Object Lock mode where objects cannot be deleted (even by root)
  • Governance Mode: S3 Object Lock mode where objects can be deleted with special permissions

Encryption Options by Service:

  • S3: SSE-S3, SSE-KMS, SSE-C, client-side encryption
  • EBS: KMS encryption (enabled by default for new volumes)
  • RDS: KMS encryption (must enable at creation, cannot enable later)
  • DynamoDB: KMS encryption (enabled by default)
  • EFS: KMS encryption (can enable at creation or later)
  • SQS: KMS encryption (optional)

Decision Points:

  • Data in transit → TLS 1.2+ (enforce with bucket policies, ALB policies)
  • Remote access → Session Manager (not SSH/RDP with bastion)
  • Direct Connect encryption → VPN over DX (layer 3) or MACsec (layer 2)
  • S3 encryption → SSE-KMS (for key rotation and audit) or SSE-S3 (simpler)
  • RDS encryption → Enable at creation (cannot enable later without migration)
  • Secret storage → Secrets Manager (with rotation) or Parameter Store (simpler)
  • Secret rotation → Secrets Manager (automatic) or Lambda (custom)
  • Compliance retention → S3 Object Lock compliance mode or Glacier Vault Lock
  • Key management → KMS (most cases) or CloudHSM (FIPS 140-2 Level 3)
  • Cross-region encryption → KMS multi-region keys
  • Backup management → AWS Backup (centralized) or service-native (simpler)

Next Steps

Before moving to Domain 6:

  1. Review the Quick Reference Card and ensure you can recall all encryption options
  2. Practice creating KMS key policies and understanding key policy evaluation
  3. Experiment with Secrets Manager rotation for RDS databases
  4. Set up S3 Object Lock and test immutability

Moving Forward:

  • Domain 6 (Management and Security Governance) will cover how to manage security at scale across multiple accounts
  • Understanding KMS key policies is essential for centralized key management
  • Data lifecycle management concepts will be applied to compliance and governance

Chapter Summary

What We Covered

This chapter covered Domain 5: Data Protection (18% of the exam), focusing on four critical task areas:

Task 5.1: Confidentiality and integrity for data in transit

  • TLS concepts and implementation for HTTPS enforcement
  • VPN concepts (IPsec) for secure connectivity
  • Secure remote access using Session Manager and EC2 Instance Connect
  • TLS certificates with CloudFront, load balancers, and other network services
  • Secure connectivity using Direct Connect and VPN gateways

Task 5.2: Confidentiality and integrity for data at rest

  • Encryption technique selection (client-side, server-side, symmetric, asymmetric)
  • Resource policies for data protection (S3, DynamoDB, KMS)
  • Preventing unauthorized public access (S3 Block Public Access, preventing public snapshots)
  • Configuring encryption at rest for AWS services (S3, RDS, DynamoDB, EBS, EFS, SQS)
  • Data integrity protection using S3 Object Lock, KMS key policies, Glacier Vault Lock

Task 5.3: Manage lifecycle of data at rest

  • S3 Lifecycle mechanisms (Object Lock, Glacier Vault Lock, Lifecycle policies)
  • Automatic lifecycle management for AWS services (S3, EBS, RDS, AMIs, CloudWatch logs)
  • AWS Backup schedules and retention policies

Task 5.4: Protect credentials, secrets, and cryptographic keys

  • Secrets Manager for secret management and automatic rotation
  • Systems Manager Parameter Store for configuration data and secrets
  • KMS key management (symmetric and asymmetric keys)
  • Customer-provided key material and custom key stores (CloudHSM)

Critical Takeaways

  1. Always encrypt data in transit: Use TLS 1.2+ for all connections. Enforce HTTPS using bucket policies, ALB listeners, and API Gateway settings.

  2. Always encrypt data at rest: Enable encryption for S3, RDS, DynamoDB, EBS, EFS, and SQS. Use KMS for key management and audit.

  3. KMS is the default choice: Use AWS managed keys for simplicity, customer managed keys for control and rotation, or CloudHSM for FIPS 140-2 Level 3 compliance.

  4. Secrets Manager for automatic rotation: Use for database credentials, API keys, and other secrets that need automatic rotation.

  5. S3 Object Lock for compliance: Use compliance mode for immutable retention (cannot be deleted even by root). Use governance mode for flexible retention.

  6. Glacier Vault Lock for long-term archival: Once locked, the vault policy cannot be changed. Use for compliance and regulatory requirements.

  7. Session Manager replaces SSH/RDP: No need for bastion hosts, public IPs, or SSH keys. Fully audited in CloudTrail.

  8. VPN over Direct Connect for encryption: Direct Connect is not encrypted by default. Use VPN over DX (layer 3) or MACsec (layer 2) for encryption.

  9. Envelope encryption for large data: KMS encrypts a data key, which encrypts the data. More efficient than encrypting large data directly with KMS.

  10. AWS Backup for centralized backup management: Create backup plans with schedules and retention policies. Use Backup Vault Lock for immutable backups.

Self-Assessment Checklist

Test yourself before moving to Domain 6. You should be able to:

Data in Transit:

  • Explain how TLS handshake works and why it's important
  • Configure HTTPS enforcement on S3 buckets using bucket policies
  • Design a VPN architecture for secure connectivity to AWS
  • Explain the difference between VPN over Direct Connect and MACsec
  • Configure Session Manager for secure remote access without SSH/RDP
  • Explain how to use ACM to manage TLS certificates
  • Design mutual TLS (mTLS) authentication for API Gateway

Data at Rest:

  • Explain the difference between SSE-S3, SSE-KMS, and SSE-C
  • Configure S3 bucket encryption with KMS
  • Enable encryption for RDS databases (at creation only)
  • Configure DynamoDB encryption with KMS
  • Explain the difference between symmetric and asymmetric KMS keys
  • Design a KMS key policy to restrict key usage
  • Configure S3 Block Public Access at account and bucket levels
  • Explain how envelope encryption works

Data Lifecycle:

  • Configure S3 Object Lock in compliance mode vs. governance mode
  • Design S3 Lifecycle policies to transition data to Glacier
  • Configure Glacier Vault Lock for immutable archival
  • Design AWS Backup plans with schedules and retention policies
  • Configure Data Lifecycle Manager for EBS snapshots
  • Explain the difference between legal hold and retention period

Secrets and Keys:

  • Configure Secrets Manager for automatic rotation of RDS credentials
  • Explain the difference between Secrets Manager and Parameter Store
  • Design a KMS key rotation strategy (automatic vs. manual)
  • Configure KMS multi-region keys for disaster recovery
  • Explain when to use CloudHSM instead of KMS
  • Design a strategy for importing customer-provided key material

Practice Questions

Recommended Practice Test Bundles:

  • Domain 5 Bundle 1: Questions 341-390 (covers all Task 5.1, 5.2, 5.3, 5.4 topics)
  • Domain 5 Bundle 2: Questions 391-430 (additional practice on weak areas)
  • Data Encryption Bundle: Questions covering KMS, Secrets Manager, Parameter Store, encryption at rest/transit

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • KMS Key Policies (if you struggled with key access control questions)
    • S3 Object Lock vs. Glacier Vault Lock (if you struggled with immutability questions)
    • Secrets Manager Rotation (if you struggled with automatic rotation questions)
    • TLS and VPN Concepts (if you struggled with data in transit questions)
  • Focus on:
    • Understanding the difference between SSE-S3, SSE-KMS, and SSE-C
    • Memorizing when to use compliance mode vs. governance mode for S3 Object Lock
    • Practicing KMS key policy writing
    • Understanding envelope encryption and when to use it

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • KMS: Key management service (symmetric and asymmetric keys)
  • CloudHSM: Hardware security module (FIPS 140-2 Level 3)
  • Secrets Manager: Secret storage with automatic rotation
  • Parameter Store: Configuration data and secrets (simpler than Secrets Manager)
  • ACM: TLS certificate management
  • S3 Object Lock: Immutable object storage (compliance or governance mode)
  • Glacier Vault Lock: Immutable vault policy for long-term archival
  • AWS Backup: Centralized backup management
  • Session Manager: Secure remote access without SSH/RDP

Key Concepts:

  • SSE-S3: Server-side encryption with S3-managed keys
  • SSE-KMS: Server-side encryption with KMS-managed keys
  • SSE-C: Server-side encryption with customer-provided keys
  • Envelope Encryption: KMS encrypts data key, data key encrypts data
  • Compliance Mode: Immutable retention (cannot be deleted even by root)
  • Governance Mode: Flexible retention (can be deleted with special permissions)
  • Automatic Rotation: KMS rotates keys annually, Secrets Manager rotates secrets on schedule
  • Multi-Region Keys: KMS keys replicated across regions for disaster recovery

Decision Points:

  • Data in transit → TLS 1.2+ (enforce with bucket policies, ALB policies)
  • Remote access → Session Manager (not SSH/RDP with bastion)
  • Direct Connect encryption → VPN over DX (layer 3) or MACsec (layer 2)
  • S3 encryption → SSE-KMS (for key rotation and audit) or SSE-S3 (simpler)
  • RDS encryption → Enable at creation (cannot enable later without migration)
  • Secret storage → Secrets Manager (with rotation) or Parameter Store (simpler)
  • Secret rotation → Secrets Manager (automatic) or Lambda (custom)
  • Compliance retention → S3 Object Lock compliance mode or Glacier Vault Lock
  • Key management → KMS (most cases) or CloudHSM (FIPS 140-2 Level 3)
  • Cross-region encryption → KMS multi-region keys
  • Backup management → AWS Backup (centralized) or service-native (simpler)

Common Patterns:

  • S3 + SSE-KMS + S3 Object Lock → Encrypted immutable storage
  • RDS + KMS + Secrets Manager → Encrypted database with rotated credentials
  • Session Manager + IAM → Secure remote access without SSH/RDP
  • VPN over Direct Connect → Encrypted hybrid connectivity
  • Secrets Manager + Lambda → Automatic secret rotation
  • AWS Backup + Backup Vault Lock → Centralized immutable backups

Chapter Summary

What We Covered

This chapter covered Domain 5: Data Protection (18% of the exam), focusing on four critical task areas:

Task 5.1: Confidentiality and integrity for data in transit

  • TLS concepts and implementation for HTTPS encryption
  • VPN concepts (IPsec) for secure site-to-site connectivity
  • Secure remote access using Systems Manager Session Manager and EC2 Instance Connect
  • TLS certificates with network services (CloudFront, load balancers, API Gateway)
  • Secure connectivity between AWS and on-premises (Direct Connect, VPN gateways, MACsec)

Task 5.2: Confidentiality and integrity for data at rest

  • Encryption technique selection (client-side, server-side, symmetric, asymmetric)
  • Resource policies to restrict access (S3 bucket policies, DynamoDB policies, KMS key policies)
  • Preventing unauthorized public access (S3 Block Public Access, preventing public snapshots/AMIs)
  • Configuring encryption at rest (S3, RDS, DynamoDB, SQS, EBS, EFS)
  • Data integrity protection (S3 Object Lock, KMS key policies, Glacier Vault Lock, Backup Vault Lock)

Task 5.3: Manage lifecycle of data at rest

  • S3 Lifecycle mechanisms (Object Lock, Glacier Vault Lock, Lifecycle policies)
  • Automatic lifecycle management (S3, EBS snapshots, RDS snapshots, AMIs, CloudWatch logs, Data Lifecycle Manager)
  • AWS Backup schedules and retention policies

Task 5.4: Protect credentials, secrets, and cryptographic keys

  • Secrets Manager for secret management and automatic rotation
  • Systems Manager Parameter Store for configuration data and secrets
  • KMS key management (symmetric and asymmetric keys, key rotation, multi-region keys)
  • Customer-provided key material (importing and removing keys)

Critical Takeaways

  1. Encrypt data in transit with TLS: Use TLS 1.2 or higher for all data in transit. Enforce HTTPS using bucket policies, load balancer listeners, and API Gateway settings.

  2. Encrypt data at rest by default: Enable encryption for S3, RDS, DynamoDB, EBS, EFS, and SQS. Use AWS-managed keys (SSE-S3, SSE-KMS) or customer-managed keys (CMK).

  3. KMS is the key management service: Use KMS to create, manage, and rotate encryption keys. KMS integrates with most AWS services for encryption at rest.

  4. Envelope encryption improves performance: Encrypt data with a data key, then encrypt the data key with a master key. This reduces the amount of data sent to KMS.

  5. S3 Object Lock prevents deletion: Use compliance mode (cannot be deleted by anyone) or governance mode (can be deleted with special permissions). Required for regulatory compliance.

  6. Secrets Manager automates rotation: Use it for database credentials, API keys, and other secrets. Automatic rotation reduces the risk of credential compromise.

  7. Parameter Store is for configuration data: Use it for non-sensitive configuration (standard tier, free) or sensitive data (advanced tier, encrypted with KMS).

  8. MACsec encrypts Direct Connect: Use MACsec for layer 2 encryption on Direct Connect connections. Provides encryption without VPN overhead.

  9. Session Manager replaces SSH: Use Systems Manager Session Manager for secure shell access without SSH keys, bastion hosts, or public IPs. All sessions logged to CloudWatch.

  10. Backup Vault Lock enforces retention: Use it to prevent deletion of backups for compliance. Similar to S3 Object Lock but for AWS Backup.

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Data in Transit:

  • Explain how TLS handshake works and why it's secure
  • Configure an ALB to enforce HTTPS and redirect HTTP to HTTPS
  • Set up a site-to-site VPN with IPsec encryption
  • Use Systems Manager Session Manager for secure shell access
  • Configure MACsec encryption for Direct Connect

Data at Rest:

  • Enable S3 bucket encryption with SSE-S3, SSE-KMS, or SSE-C
  • Create a KMS customer-managed key with key policy
  • Configure RDS encryption at rest with KMS
  • Implement S3 Object Lock in compliance mode
  • Prevent public access to S3 buckets using Block Public Access

Data Lifecycle:

  • Create an S3 Lifecycle policy to transition objects to Glacier
  • Configure Data Lifecycle Manager for automated EBS snapshot management
  • Set up AWS Backup with retention policies
  • Implement Glacier Vault Lock for compliance
  • Design a data retention strategy that meets regulatory requirements

Secrets and Keys:

  • Store database credentials in Secrets Manager with automatic rotation
  • Use Parameter Store for application configuration data
  • Create a KMS key with automatic rotation enabled
  • Implement cross-account KMS key access
  • Import customer-provided key material into KMS

Practice Questions

Try these from your practice test bundles:

  • Domain 5 Bundle 1: Questions 1-25 (focus on encryption and data protection)
  • Domain 5 Bundle 2: Questions 26-50 (focus on lifecycle and secrets management)
  • Data Encryption Bundle: Questions covering KMS, Secrets Manager, Parameter Store, encryption at rest/transit
  • Full Practice Test 1: Domain 5 questions (9 questions, 18% of exam)

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review the differences between SSE-S3, SSE-KMS, and SSE-C
  • Practice creating KMS key policies and understanding key permissions
  • Focus on understanding S3 Object Lock modes (compliance vs governance)
  • Revisit Secrets Manager rotation and Parameter Store use cases

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • KMS: Key Management Service for encryption keys
  • Secrets Manager: Automatic secret rotation for credentials
  • Parameter Store: Configuration data and secrets storage
  • S3 Object Lock: Immutable object storage for compliance
  • Glacier Vault Lock: Immutable archive storage
  • Backup Vault Lock: Immutable backup storage
  • ACM: AWS Certificate Manager for TLS certificates
  • Systems Manager Session Manager: Secure shell access without SSH

Key Concepts:

  • TLS: Transport Layer Security for data in transit encryption
  • Envelope Encryption: Encrypt data with data key, encrypt data key with master key
  • SSE-S3: Server-side encryption with S3-managed keys
  • SSE-KMS: Server-side encryption with KMS-managed keys
  • SSE-C: Server-side encryption with customer-provided keys
  • Client-Side Encryption: Encrypt data before sending to AWS
  • Symmetric Encryption: Same key for encryption and decryption (AES-256)
  • Asymmetric Encryption: Public key for encryption, private key for decryption (RSA)
  • Key Rotation: Automatically creating new key versions (KMS does this annually)
  • MACsec: Media Access Control Security for layer 2 encryption

Encryption Options:

  • S3: SSE-S3 (default), SSE-KMS (audit trail), SSE-C (customer keys), client-side
  • RDS: KMS encryption at rest (must enable at creation)
  • DynamoDB: KMS encryption at rest (default with AWS-managed key)
  • EBS: KMS encryption at rest (can enable by default for account)
  • EFS: KMS encryption at rest (enable at creation)
  • SQS: KMS encryption at rest (optional)

Decision Points:

  • Need data in transit encryption → TLS 1.2+ (HTTPS, VPN, MACsec)
  • Need data at rest encryption → KMS with SSE-KMS or AWS-managed keys
  • Need audit trail for key usage → KMS customer-managed keys (CloudTrail logs)
  • Need to prevent deletion → S3 Object Lock (compliance mode)
  • Need automatic secret rotation → Secrets Manager
  • Need configuration data → Parameter Store (standard tier, free)
  • Need secure shell access → Systems Manager Session Manager
  • Need TLS certificates → ACM (free, auto-renewal)
  • Need Direct Connect encryption → MACsec or VPN over Direct Connect

Common Troubleshooting:

  • KMS access denied → Check key policy, IAM policy, grants
  • S3 encryption not working → Check bucket policy, default encryption settings
  • Secrets Manager rotation failing → Check Lambda function, VPC endpoints, IAM permissions
  • Session Manager not connecting → Check SSM agent, IAM permissions, VPC endpoints
  • TLS certificate errors → Check ACM certificate validation, domain ownership

You're now ready for Chapter 6: Management and Security Governance!

The next chapter will teach you how to manage security at scale across multiple accounts.


Chapter 6: Management and Security Governance (14% of exam)

Chapter Overview

What you'll learn:

  • AWS Organizations and multi-account strategies
  • Service Control Policies (SCPs)
  • AWS Control Tower for governance
  • Compliance monitoring with Config
  • Cost and security optimization

Time to complete: 8-10 hours
Prerequisites: Chapter 0 (Fundamentals), Chapter 2 (Config basics)

Why this domain matters: Governance ensures consistent security across all AWS accounts. This domain represents 14% of the exam and tests your ability to implement multi-account strategies, enforce policies, and maintain compliance.


Section 1: AWS Organizations

What is AWS Organizations

What it is: AWS Organizations enables you to centrally manage multiple AWS accounts, consolidate billing, and apply policies across accounts.

Why it matters: Managing security policies individually in each account is impractical. Organizations provides centralized control and policy enforcement.

Key Features:

  • Organizational Units (OUs): Group accounts by function (Dev, Test, Prod)
  • Service Control Policies (SCPs): Control maximum permissions for accounts
  • Consolidated Billing: Single bill for all accounts
  • Delegated Administration: Delegate service management to specific accounts

Service Control Policies (SCPs)

What it is: SCPs are policies that control the maximum available permissions for accounts in an organization. They act as guardrails.

How they work: SCPs don't grant permissions - they set boundaries. Even if an IAM policy allows an action, an SCP can prevent it.

Example SCP - Prevent Root Account Usage:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Deny",
      "Action": "*",
      "Resource": "*",
      "Condition": {
        "StringLike": {
          "aws:PrincipalArn": "arn:aws:iam::*:root"
        }
      }
    }
  ]
}

This SCP prevents the root user from performing any actions, enforcing the best practice of not using root.

Detailed Example: Enforcing Region Restrictions

A company must ensure resources are only created in US regions for compliance. Here's how they use SCPs: (1) They create an SCP that denies all actions in non-US regions. (2) They attach the SCP to the root of their organization, applying it to all accounts. (3) A developer attempts to launch an EC2 instance in eu-west-1 (Ireland). (4) The action is denied by the SCP, even though the developer's IAM policy allows it. (5) The developer can only create resources in us-east-1 and us-west-2. (6) The SCP enforces the compliance requirement across all accounts without modifying individual IAM policies. SCPs provided centralized policy enforcement.


Section 2: AWS Control Tower

What is Control Tower

What it is: AWS Control Tower automates the setup of a secure, multi-account AWS environment based on best practices.

Why it matters: Setting up a secure multi-account environment manually is complex and error-prone. Control Tower automates this process.

Key Features:

  • Landing Zone: Pre-configured multi-account environment
  • Guardrails: Preventive (SCPs) and detective (Config rules) controls
  • Account Factory: Automated account provisioning
  • Dashboard: Centralized compliance visibility

Guardrail Types:

  • Mandatory: Always enforced (e.g., disallow public read access to S3)
  • Strongly Recommended: Best practices (e.g., enable MFA for root user)
  • Elective: Optional controls (e.g., disallow specific instance types)

Detailed Example: Setting Up Governance with Control Tower

A company wants to implement governance for 50 AWS accounts. Here's how they use Control Tower: (1) They enable Control Tower, which creates a landing zone with security and logging accounts. (2) Control Tower applies mandatory guardrails: prevent public S3 buckets, enable CloudTrail, enable Config. (3) They enable strongly recommended guardrails: MFA for root, encrypted EBS volumes. (4) They use Account Factory to provision new accounts with pre-configured security settings. (5) The compliance dashboard shows all accounts are compliant with guardrails. (6) When a developer creates a public S3 bucket, the preventive guardrail blocks it. (7) Control Tower automated governance across all accounts, ensuring consistent security.


Section 3: Compliance Monitoring

AWS Config for Compliance

What it is: AWS Config continuously monitors resource configurations and evaluates them against desired settings (Config Rules).

Why it matters: Compliance requires proving resources meet security standards. Config automates compliance checking and reporting.

Managed Config Rules (Examples):

  • encrypted-volumes: Ensure EBS volumes are encrypted
  • s3-bucket-public-read-prohibited: Ensure S3 buckets are not public
  • iam-password-policy: Ensure IAM password policy meets requirements
  • restricted-ssh: Ensure security groups don't allow SSH from 0.0.0.0/0

Conformance Packs: Pre-packaged sets of Config rules for compliance frameworks (PCI DSS, HIPAA, CIS).

Detailed Example: PCI DSS Compliance

A company must demonstrate PCI DSS compliance. Here's how they use Config: (1) They deploy the PCI DSS Conformance Pack, which includes 30+ Config rules. (2) Config evaluates all resources against the rules. (3) The compliance dashboard shows 95% compliance. (4) They investigate non-compliant resources: 5 unencrypted EBS volumes. (5) They encrypt the volumes and Config marks them as compliant. (6) They generate a compliance report for auditors showing 100% compliance. (7) Config continuously monitors for drift and alerts on non-compliance. Config automated PCI DSS compliance monitoring.


Section 4: Cost and Security Optimization

AWS Trusted Advisor

What it is: Trusted Advisor provides real-time guidance to help you provision resources following AWS best practices.

Security Checks (Examples):

  • Security groups with unrestricted access
  • IAM users with access keys not rotated
  • S3 buckets with public access
  • MFA not enabled on root account
  • Exposed access keys

Detailed Example: Security Optimization

A security team uses Trusted Advisor to identify security issues. Here's what they find: (1) Trusted Advisor shows 10 security groups allow SSH from 0.0.0.0/0. (2) They update security groups to restrict SSH to corporate IP ranges. (3) Trusted Advisor shows 5 IAM users haven't rotated access keys in 90+ days. (4) They rotate the keys and implement automatic rotation. (5) Trusted Advisor shows 3 S3 buckets have public read access. (6) They remove public access and enable S3 Block Public Access. (7) All Trusted Advisor security checks are now green. Trusted Advisor identified security gaps that needed remediation.


Chapter Summary

What We Covered

  • AWS Organizations: Multi-account management, SCPs
  • Control Tower: Automated governance, guardrails
  • Config: Compliance monitoring, conformance packs
  • Trusted Advisor: Security optimization

Critical Takeaways

  1. Use Organizations for multi-account: Centralized management and policy enforcement
  2. SCPs set boundaries: They limit maximum permissions, don't grant them
  3. Control Tower automates governance: Use it for new multi-account environments
  4. Config for compliance: Continuous monitoring and automated reporting
  5. Trusted Advisor for optimization: Regular security checks and recommendations

Self-Assessment Checklist

  • I understand how SCPs work and their relationship to IAM policies
  • I can explain the difference between preventive and detective guardrails
  • I know how to use Config rules for compliance monitoring
  • I understand when to use Control Tower vs manual Organizations setup

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (Organizations and Control Tower)
  • Domain 6 Bundle 2: Questions 26-50 (Compliance and optimization)
  • Expected score: 70%+ to proceed

Next Chapter: Chapter 7 - Integration and Cross-Domain Scenarios

Chapter 6: Management and Security Governance (14% of exam)

Chapter Overview

What you'll learn:

  • Multi-account strategies with AWS Organizations
  • Centralized security management and compliance
  • Infrastructure as Code security best practices
  • Compliance monitoring and evidence collection

Time to complete: 6-8 hours
Prerequisites: Chapters 0-5 (especially IAM and logging concepts)


Section 1: Multi-Account Strategy and Centralized Management

Introduction

The problem: Managing security across multiple AWS accounts is complex. Each account has separate IAM policies, security configurations, and logging. Without centralized control, security policies are inconsistent, compliance is difficult to verify, and security gaps emerge.

The solution: AWS Organizations provides centralized management of multiple accounts with Service Control Policies (SCPs) for guardrails. AWS Control Tower automates account provisioning with pre-configured security baselines. Delegated administration allows centralized security service management.

Why it's tested: The exam tests your ability to design multi-account strategies, implement SCPs for security guardrails, deploy Control Tower, and centralize security management. You must understand how to enforce security policies across an organization.

Core Concepts

AWS Organizations and Multi-Account Architecture

What it is: AWS Organizations is a service that enables you to centrally manage and govern multiple AWS accounts. You create an organization with a management account (formerly master account) and add member accounts organized into Organizational Units (OUs). Service Control Policies (SCPs) define maximum permissions for accounts.

Why it exists: Organizations need multiple AWS accounts for security isolation (separate production from development), cost allocation (track spending by team), and compliance (isolate regulated workloads). Managing these accounts individually is operationally complex. Organizations provides centralized management while maintaining account isolation.

Real-world analogy: AWS Organizations is like a corporate structure with a headquarters (management account) and divisions (OUs). The headquarters sets company-wide policies (SCPs) that all divisions must follow. Each division (account) can have its own internal rules (IAM policies), but they cannot violate corporate policies.

How Organizations works (Detailed step-by-step):

  1. Organization Creation: You create an organization from an existing AWS account, which becomes the management account. This account has full control over the organization and pays all member account bills (consolidated billing).

  2. Account Invitation/Creation: You invite existing AWS accounts to join the organization, or create new accounts directly within the organization. New accounts are automatically part of the organization with no invitation needed.

  3. Organizational Unit Structure: You create OUs to group accounts logically (by environment, team, or function). OUs can be nested up to 5 levels deep. Example structure: Root → Production OU → Application OU → Account.

  4. Service Control Policy Creation: You create SCPs that define maximum permissions. SCPs are JSON policies similar to IAM policies but apply to entire accounts or OUs. They act as permission boundaries - even if an IAM policy allows an action, the SCP can deny it.

  5. SCP Attachment: You attach SCPs to the root, OUs, or individual accounts. SCPs inherit down the OU hierarchy. An account's effective permissions are the intersection of all SCPs in its path to the root.

  6. Policy Evaluation: When a user in a member account makes an AWS API call, AWS evaluates: (1) SCPs (deny overrides allow), (2) IAM permission boundaries, (3) IAM policies. The action is allowed only if all three permit it.

  7. Consolidated Billing: All member account charges roll up to the management account. You get volume discounts across all accounts and can use Reserved Instances and Savings Plans across the organization.

  8. Delegated Administration: You can delegate administration of AWS services (Security Hub, GuardDuty, Macie) to a member account. This allows centralized security management without using the management account for day-to-day operations.

📊 AWS Organizations Architecture Diagram:

graph TB
    ROOT[Organization Root<br/>SCP: DenyLeaveOrganization]
    
    subgraph "Management Account"
        MGMT[Management Account<br/>Billing & Organization Control]
    end
    
    subgraph "Security OU"
        SEC_SCP[SCP: RequireMFA<br/>DenyRootAccess]
        LOG[Log Archive Account]
        AUDIT[Security Audit Account]
    end
    
    subgraph "Production OU"
        PROD_SCP[SCP: DenyRegionRestriction<br/>RequireEncryption]
        PROD1[Production App 1]
        PROD2[Production App 2]
    end
    
    subgraph "Development OU"
        DEV_SCP[SCP: AllowAllServices]
        DEV1[Dev Account 1]
        DEV2[Dev Account 2]
    end
    
    ROOT --> MGMT
    ROOT --> SEC_SCP
    ROOT --> PROD_SCP
    ROOT --> DEV_SCP
    
    SEC_SCP --> LOG
    SEC_SCP --> AUDIT
    PROD_SCP --> PROD1
    PROD_SCP --> PROD2
    DEV_SCP --> DEV1
    DEV_SCP --> DEV2

    style MGMT fill:#e1f5fe
    style LOG fill:#c8e6c9
    style AUDIT fill:#c8e6c9
    style PROD1 fill:#fff3e0
    style PROD2 fill:#fff3e0
    style DEV1 fill:#f3e5f5
    style DEV2 fill:#f3e5f5

See: diagrams/07_domain6_organizations_architecture.mmd

Diagram Explanation (Detailed):
The AWS Organizations architecture diagram shows a typical multi-account structure. At the top is the Organization Root with an SCP that prevents accounts from leaving the organization. The Management Account (blue) controls the entire organization and handles consolidated billing. The Security OU (green) contains specialized security accounts: a Log Archive account for centralized logging and a Security Audit account for security tooling. An SCP on the Security OU requires MFA and denies root account usage. The Production OU (orange) contains production application accounts with an SCP that restricts regions and requires encryption. The Development OU (purple) has more permissive SCPs allowing developers flexibility. SCPs inherit down the hierarchy - accounts in Production OU are subject to both the root SCP and the Production OU SCP. This structure provides security isolation (separate accounts), centralized control (SCPs), and operational flexibility (different policies per OU). The Security OU accounts are typically managed by the security team with delegated administration for security services.

Detailed Example 1: Preventing Data Exfiltration with SCPs
Your organization wants to prevent data exfiltration by restricting which AWS regions can be used. You create an SCP that denies all actions in regions outside us-east-1 and us-west-2. The SCP uses a Deny statement with a condition: "Condition": {"StringNotEquals": {"aws:RequestedRegion": ["us-east-1", "us-west-2"]}}. You attach this SCP to the Production OU. Now, even if a user has full AdministratorAccess in their IAM policy, they cannot create resources in eu-west-1 or any other region. If an attacker compromises credentials and tries to exfiltrate data by copying it to an S3 bucket in a different region, the API call is denied by the SCP. The SCP also includes exceptions for global services (IAM, CloudFront, Route 53) that don't operate in specific regions. This provides a strong security control that cannot be bypassed by IAM policies, protecting against both insider threats and compromised credentials.

Detailed Example 2: Enforcing Encryption with SCPs
Your compliance team requires all S3 buckets to use encryption at rest. You create an SCP that denies s3:PutObject unless the request includes encryption headers. The SCP includes a condition: "Condition": {"StringNotEquals": {"s3:x-amz-server-side-encryption": ["AES256", "aws:kms"]}}. You attach this SCP to the root of your organization, applying it to all accounts. Now, any attempt to upload an unencrypted object to S3 is denied, regardless of IAM permissions. Developers must specify encryption when uploading: aws s3 cp file.txt s3://bucket/ --server-side-encryption AES256. This enforces encryption organization-wide without relying on individual developers to remember. You also create an SCP that requires EBS volumes to be encrypted: deny ec2:RunInstances unless ec2:Encrypted is true. These SCPs provide defense-in-depth - even if someone misconfigures an IAM policy or application, encryption is still enforced.

Detailed Example 3: Multi-Account Security with Delegated Administration
Your organization has 50 AWS accounts and needs centralized security management. You create a dedicated Security account in the Security OU. You enable AWS Organizations integration for Security Hub, GuardDuty, and Macie. You designate the Security account as the delegated administrator for these services. From the Security account, you enable Security Hub in all 50 accounts automatically. Security Hub aggregates findings from all accounts into the Security account's dashboard. You enable GuardDuty across all accounts, with findings sent to the Security account. You configure Macie to scan S3 buckets in all accounts for sensitive data. The Security team can now view and manage security across all accounts from a single pane of glass. You create an SCP that prevents member accounts from disabling Security Hub, GuardDuty, or Macie. This ensures security monitoring cannot be bypassed. CloudTrail logs from all accounts are sent to a centralized S3 bucket in the Log Archive account with Object Lock enabled, preventing tampering.

Must Know (Critical Facts):

  • Management account has full control over organization - protect it with MFA and restrict access
  • SCPs define maximum permissions - they filter IAM policies but don't grant permissions
  • SCPs do not affect the management account - management account is not restricted by SCPs
  • Deny in SCP always wins - explicit deny cannot be overridden by IAM allow
  • SCPs inherit down OU hierarchy - account receives all SCPs from root to its OU
  • Consolidated billing provides volume discounts and shared Reserved Instances across accounts
  • Delegated administration allows security management without using management account

When to use (Comprehensive):

  • ✅ Use Organizations when: You have multiple AWS accounts and need centralized management
  • ✅ Use SCPs when: You need to enforce security guardrails that cannot be bypassed by IAM
  • ✅ Use OUs when: You need to group accounts by environment, team, or compliance requirements
  • ✅ Use delegated administration when: You want to centralize security services without using management account
  • ✅ Use consolidated billing when: You want volume discounts and simplified billing across accounts
  • ❌ Don't use SCPs when: You need to grant permissions - use IAM policies instead
  • ❌ Don't use management account when: Performing day-to-day operations - use member accounts

Limitations & Constraints:

  • Maximum 5 levels of OU nesting
  • Maximum 1,000 accounts per organization (can request increase)
  • Maximum 5 SCPs attached per account or OU
  • SCP size limit: 5,120 characters
  • SCPs do not affect service-linked roles
  • Cannot remove management account from organization

💡 Tips for Understanding:

  • Think of SCPs as "permission boundaries for accounts" - they limit what IAM can allow
  • Remember: SCPs filter, IAM grants - both must allow for action to succeed
  • Management account is special - not restricted by SCPs, has full control
  • Deny always wins - explicit deny in SCP cannot be overridden

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking SCPs grant permissions like IAM policies
    • Why it's wrong: SCPs only restrict permissions, they never grant them
    • Correct understanding: SCPs are filters that limit maximum permissions. You still need IAM policies to grant actual permissions. SCP allows + IAM allows = action allowed. SCP denies = action denied regardless of IAM
  • Mistake 2: Assuming SCPs apply to management account
    • Why it's wrong: Management account is exempt from all SCPs for safety
    • Correct understanding: SCPs only affect member accounts. Management account has unrestricted access. This is why you should minimize use of management account and use delegated administration
  • Mistake 3: Forgetting that SCPs inherit down the OU hierarchy
    • Why it's wrong: An account may be restricted by SCPs attached to parent OUs
    • Correct understanding: An account's effective SCP is the intersection of all SCPs from root to the account. If any SCP in the path denies an action, it's denied

🔗 Connections to Other Topics:

  • Relates to IAM because: SCPs work together with IAM policies to determine effective permissions
  • Builds on CloudTrail by: Logging all organization management actions for audit
  • Often used with Control Tower to: Automate account provisioning with security baselines
  • Integrates with Security Hub to: Aggregate security findings across all accounts

Troubleshooting Common Issues:

  • Issue 1: User has IAM permissions but action is denied
    • Solution: Check SCPs attached to account and parent OUs. An SCP may be denying the action. Use IAM policy simulator to test effective permissions
  • Issue 2: Cannot enable service in member account
    • Solution: Check if service requires Organizations integration. Some services (Security Hub, GuardDuty) must be enabled from management account or delegated administrator
  • Issue 3: Consolidated billing not showing expected discounts
    • Solution: Verify all accounts are in same organization. Reserved Instances and Savings Plans share across organization. Check that sharing is enabled in billing preferences

AWS Control Tower for Automated Account Provisioning

What it is: AWS Control Tower is a service that automates the setup of a secure, multi-account AWS environment based on AWS best practices. It provides pre-configured guardrails (SCPs and AWS Config rules), automated account provisioning through Account Factory, and a dashboard for governance visibility.

Why it exists: Setting up a secure multi-account environment manually is complex and error-prone. Organizations need consistent security baselines across accounts, automated account provisioning for teams, and ongoing compliance monitoring. Control Tower automates these tasks, reducing setup time from weeks to hours.

Real-world analogy: Control Tower is like a construction company that builds houses according to building codes. Instead of each homeowner figuring out electrical wiring, plumbing, and structural requirements (manual account setup), the construction company provides pre-built houses that meet all safety codes (pre-configured security baselines). You can still customize the interior (account-specific configurations), but the foundation and structure are standardized and secure.

How Control Tower works (Detailed step-by-step):

  1. Landing Zone Setup: You launch Control Tower from the management account. It creates a "landing zone" - a well-architected multi-account environment with two core accounts: Log Archive (for centralized logging) and Audit (for security and compliance).

  2. Organizational Unit Creation: Control Tower creates OUs: Security OU (for core accounts), Sandbox OU (for experimentation), and optionally custom OUs. These OUs have pre-configured SCPs.

  3. Guardrail Deployment: Control Tower deploys guardrails - preventive (SCPs) and detective (AWS Config rules). Mandatory guardrails are always enabled (e.g., disallow public read access to Log Archive bucket). Strongly recommended and elective guardrails can be enabled as needed.

  4. Account Factory Configuration: You configure Account Factory with account templates including VPC configuration, region settings, and guardrails. Account Factory uses AWS Service Catalog to provision accounts.

  5. Account Provisioning: When a user requests a new account through Account Factory, Control Tower: (a) Creates the account in Organizations, (b) Applies baseline configurations (CloudTrail, AWS Config, guardrails), (c) Creates a VPC with public/private subnets, (d) Enrolls the account in Control Tower management.

  6. Drift Detection: Control Tower continuously monitors for drift - changes that violate guardrails or baseline configurations. If someone manually disables CloudTrail or modifies an SCP, Control Tower detects and alerts on the drift.

  7. Compliance Dashboard: The Control Tower dashboard shows compliance status across all accounts, guardrail violations, and drift. You can see which accounts are compliant and which need remediation.

  8. Customization: You can customize Control Tower using Account Factory Customization (AFC) to deploy additional resources (security tools, monitoring) when accounts are provisioned.

📊 Control Tower Landing Zone Diagram:

graph TB
    subgraph "Management Account"
        MGMT[Management Account<br/>Control Tower Console]
        AF[Account Factory<br/>Service Catalog]
    end
    
    subgraph "Security OU"
        LOG[Log Archive Account<br/>Centralized CloudTrail<br/>Config Logs]
        AUDIT[Audit Account<br/>Security Hub<br/>GuardDuty<br/>Config Aggregator]
    end
    
    subgraph "Sandbox OU"
        SAND1[Sandbox Account 1<br/>Guardrails: Elective]
        SAND2[Sandbox Account 2<br/>Guardrails: Elective]
    end
    
    subgraph "Production OU"
        PROD1[Production Account 1<br/>Guardrails: Mandatory + Strongly Recommended]
        PROD2[Production Account 2<br/>Guardrails: Mandatory + Strongly Recommended]
    end
    
    subgraph "Guardrails"
        PREVENT[Preventive Guardrails<br/>SCPs]
        DETECT[Detective Guardrails<br/>AWS Config Rules]
    end
    
    MGMT --> AF
    AF -.Provisions.-> SAND1
    AF -.Provisions.-> SAND2
    AF -.Provisions.-> PROD1
    AF -.Provisions.-> PROD2
    
    PREVENT --> SAND1
    PREVENT --> SAND2
    PREVENT --> PROD1
    PREVENT --> PROD2
    
    DETECT --> SAND1
    DETECT --> SAND2
    DETECT --> PROD1
    DETECT --> PROD2
    
    SAND1 -.Logs.-> LOG
    SAND2 -.Logs.-> LOG
    PROD1 -.Logs.-> LOG
    PROD2 -.Logs.-> LOG
    
    SAND1 -.Compliance Data.-> AUDIT
    SAND2 -.Compliance Data.-> AUDIT
    PROD1 -.Compliance Data.-> AUDIT
    PROD2 -.Compliance Data.-> AUDIT

    style MGMT fill:#e1f5fe
    style LOG fill:#c8e6c9
    style AUDIT fill:#c8e6c9
    style SAND1 fill:#f3e5f5
    style SAND2 fill:#f3e5f5
    style PROD1 fill:#fff3e0
    style PROD2 fill:#fff3e0

See: diagrams/07_domain6_control_tower_landing_zone.mmd

Diagram Explanation (Detailed):
The Control Tower Landing Zone diagram shows the automated multi-account environment. The Management Account (blue) hosts the Control Tower console and Account Factory (Service Catalog). The Security OU contains two core accounts: Log Archive (green) receives all CloudTrail and Config logs from all accounts, and Audit (green) hosts security tools like Security Hub, GuardDuty, and Config Aggregator for compliance monitoring. The Sandbox OU (purple) contains accounts for experimentation with elective guardrails - developers have more freedom here. The Production OU (orange) contains production accounts with mandatory and strongly recommended guardrails enforced. Account Factory provisions new accounts automatically with baseline configurations. Preventive guardrails (SCPs) prevent non-compliant actions, while detective guardrails (Config rules) detect violations. All accounts send logs to the Log Archive account and compliance data to the Audit account. This architecture provides consistent security baselines, centralized logging, and automated compliance monitoring across all accounts.

Detailed Example 1: Setting Up Control Tower for Enterprise
Your enterprise is migrating to AWS and needs a secure multi-account foundation. You launch Control Tower from your management account. Control Tower creates the landing zone with Log Archive and Audit accounts in the Security OU. It enables mandatory guardrails like "Disallow changes to CloudTrail" and "Detect whether MFA is enabled for root user". You enable strongly recommended guardrails like "Disallow internet connection through RDP" and "Detect whether public read access to S3 buckets is allowed". You create a Production OU and enable additional guardrails requiring encryption. You configure Account Factory with a VPC template (3 public subnets, 3 private subnets, NAT gateways). When the development team requests a new account, they submit a request through Service Catalog. Account Factory provisions the account in 20 minutes with CloudTrail enabled, Config recording, VPC configured, and all guardrails applied. The account appears in the Control Tower dashboard showing compliance status. All logs flow to the Log Archive account. The Audit account aggregates security findings. Your security team can see compliance across all accounts from a single dashboard.

Detailed Example 2: Detecting and Remediating Drift
Your organization uses Control Tower to manage 30 accounts. A developer in a production account manually disables CloudTrail to reduce costs (violating a mandatory guardrail). Control Tower's drift detection identifies this change within minutes. The Control Tower dashboard shows the account in "Drifted" status with details: "CloudTrail disabled in us-east-1". An EventBridge rule triggers when drift is detected, sending an SNS notification to the security team. The security team investigates and finds the developer disabled CloudTrail. They re-enable CloudTrail and educate the developer on the importance of audit logging. To prevent future occurrences, they implement an SCP that denies cloudtrail:StopLogging for all users except the security team. Control Tower's drift detection ensures security baselines are maintained and violations are quickly identified and remediated.

Detailed Example 3: Customizing Account Factory with Security Tools
Your security team wants all new accounts to automatically have Security Hub, GuardDuty, and a specific set of Config rules enabled. You use Account Factory Customization (AFC) to extend the baseline. You create a CloudFormation template that enables Security Hub, GuardDuty, and deploys custom Config rules. You package this as a Service Catalog product and configure Account Factory to deploy it during account provisioning. Now, when Account Factory provisions a new account, it: (1) Creates the account with Control Tower baselines, (2) Deploys your custom CloudFormation template enabling security tools, (3) Registers the account with the Audit account as the delegated administrator for Security Hub and GuardDuty. New accounts are automatically enrolled in centralized security monitoring without manual configuration. This ensures consistent security tooling across all accounts and reduces the time to secure new accounts from hours to minutes.

Must Know (Critical Facts):

  • Control Tower creates two core accounts: Log Archive (logging) and Audit (security/compliance)
  • Guardrails are preventive (SCPs) or detective (Config rules)
  • Mandatory guardrails cannot be disabled - always enforced
  • Account Factory automates account provisioning with baseline configurations
  • Drift detection identifies changes that violate guardrails or baselines
  • Control Tower requires Organizations - cannot be used without Organizations
  • Landing zone setup takes 30-60 minutes - creates OUs, accounts, and guardrails

When to use (Comprehensive):

  • ✅ Use Control Tower when: Setting up a new multi-account environment from scratch
  • ✅ Use Control Tower when: You need automated account provisioning with security baselines
  • ✅ Use Control Tower when: You want pre-configured guardrails based on AWS best practices
  • ✅ Use Control Tower when: You need centralized compliance visibility across accounts
  • ✅ Use Account Factory when: Teams need to self-service provision AWS accounts
  • ❌ Don't use Control Tower when: You have complex existing Organizations structure - migration is difficult
  • ❌ Don't use Control Tower when: You need highly customized account configurations - Control Tower is opinionated

Limitations & Constraints:

  • Control Tower must be set up in management account - cannot use delegated administrator
  • Cannot easily migrate existing Organizations to Control Tower - requires careful planning
  • Guardrails are region-specific - must enable in each region where you operate
  • Account Factory provisions accounts in single region - multi-region requires customization
  • Maximum 300 accounts per landing zone (can request increase)

💡 Tips for Understanding:

  • Think of Control Tower as "AWS account factory with security built-in"
  • Mandatory guardrails = must have, Strongly recommended = should have, Elective = nice to have
  • Drift = deviation from baseline - Control Tower detects and alerts
  • Landing zone = the entire multi-account environment created by Control Tower

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Trying to enable Control Tower in existing complex Organizations
    • Why it's wrong: Control Tower expects specific OU structure and may conflict with existing setup
    • Correct understanding: Control Tower works best for new environments. For existing Organizations, carefully plan migration or use Organizations + SCPs without Control Tower
  • Mistake 2: Thinking Control Tower replaces all security tools
    • Why it's wrong: Control Tower provides baseline security, not comprehensive security
    • Correct understanding: Control Tower provides foundational guardrails and account baselines. You still need to deploy security tools (Security Hub, GuardDuty, WAF) and implement application-level security
  • Mistake 3: Assuming drift detection automatically remediates issues
    • Why it's wrong: Drift detection only alerts, doesn't fix
    • Correct understanding: Control Tower detects drift and alerts you. You must manually remediate or implement automated remediation using EventBridge and Lambda

🔗 Connections to Other Topics:

  • Relates to Organizations because: Control Tower is built on top of Organizations
  • Builds on CloudTrail by: Automatically enabling CloudTrail in all accounts
  • Often used with Service Catalog to: Provide Account Factory for self-service provisioning
  • Integrates with Config to: Implement detective guardrails and compliance monitoring

Troubleshooting Common Issues:

  • Issue 1: Control Tower setup fails with "Organizations not enabled"
    • Solution: Enable AWS Organizations before launching Control Tower. Control Tower requires Organizations to be enabled in the management account
  • Issue 2: Account Factory provisioning fails
    • Solution: Check Service Catalog permissions. User needs AWSServiceCatalogEndUserFullAccess policy. Verify Account Factory portfolio is shared with user
  • Issue 3: Guardrail shows as "Not Enabled" in some accounts
    • Solution: Guardrails are region-specific. Enable guardrails in all regions where you have resources. Check that accounts are enrolled in Control Tower

Section 2: Compliance Monitoring and Evidence Collection

Introduction

The problem: Organizations must demonstrate compliance with security standards (CIS, PCI-DSS, HIPAA) and regulatory requirements. Manual compliance audits are time-consuming, error-prone, and provide only point-in-time snapshots. Collecting evidence for audits requires significant effort.

The solution: AWS Config continuously monitors resource configurations and evaluates them against compliance rules. Security Hub aggregates findings from multiple services and maps them to compliance frameworks. AWS Audit Manager automates evidence collection for audits. These services provide continuous compliance monitoring and automated evidence gathering.

Why it's tested: The exam tests your ability to implement continuous compliance monitoring, create custom Config rules, use Security Hub for compliance standards, and automate evidence collection. You must understand how to evaluate compliance and respond to violations.

Core Concepts

AWS Config for Continuous Compliance

What it is: AWS Config is a service that continuously monitors and records AWS resource configurations. It evaluates resources against Config rules (desired configurations) and reports compliance status. Config provides configuration history, change tracking, and compliance dashboards.

Why it exists: Organizations need to know the current state of their AWS resources, track configuration changes over time, and ensure resources comply with security policies. Manual configuration audits don't scale and miss changes between audits. Config automates this process with continuous monitoring.

Real-world analogy: AWS Config is like a security camera system with motion detection in a building. The cameras continuously record everything (configuration history). Motion detection alerts when something changes (configuration changes). Security rules check if changes violate policies (compliance rules). You can review footage to see what happened and when (configuration timeline).

How AWS Config works (Detailed step-by-step):

  1. Config Recorder Setup: You enable AWS Config in each region and account. The Config recorder starts tracking resource configurations. You specify which resource types to record (all resources or specific types).

  2. Configuration Snapshots: Config takes periodic snapshots of resource configurations (every 6 hours by default). It also records configuration changes immediately when they occur. Snapshots are stored in an S3 bucket.

  3. Configuration Items: When a resource changes, Config creates a Configuration Item (CI) - a JSON document containing the resource's configuration, relationships, and metadata. CIs are stored in S3 and can be queried.

  4. Config Rules Creation: You create Config rules that define desired configurations. Rules can be AWS-managed (pre-built) or custom (Lambda functions). Example: "S3 buckets must have encryption enabled" or "EC2 instances must use approved AMIs".

  5. Compliance Evaluation: Config evaluates resources against rules. Evaluation triggers when: (a) Configuration changes (change-triggered), (b) Periodic schedule (periodic), or (c) Manual trigger. Config determines if the resource is compliant or non-compliant.

  6. Compliance Dashboard: Config provides a dashboard showing compliance status across all rules. You can see which resources are non-compliant and drill down into details. Compliance data is also available via API.

  7. Remediation Actions: You can configure automatic remediation for non-compliant resources. Config invokes Systems Manager Automation documents to fix issues. Example: If S3 bucket lacks encryption, automatically enable it.

  8. Configuration Timeline: For any resource, you can view its configuration timeline showing all changes over time. This is valuable for troubleshooting and forensic analysis.

📊 AWS Config Compliance Monitoring Diagram:

graph TB
    subgraph "AWS Resources"
        S3[S3 Buckets]
        EC2[EC2 Instances]
        RDS[RDS Databases]
        IAM[IAM Roles]
    end
    
    subgraph "AWS Config"
        RECORDER[Config Recorder<br/>Tracks Changes]
        RULES[Config Rules<br/>Compliance Checks]
        EVAL[Compliance Evaluation<br/>Engine]
    end
    
    subgraph "Storage & Reporting"
        S3BUCKET[S3 Bucket<br/>Configuration History]
        DASHBOARD[Config Dashboard<br/>Compliance Status]
        SNS[SNS Topic<br/>Compliance Alerts]
    end
    
    subgraph "Remediation"
        SSM[Systems Manager<br/>Automation]
        LAMBDA[Lambda Function<br/>Custom Remediation]
    end
    
    S3 --> RECORDER
    EC2 --> RECORDER
    RDS --> RECORDER
    IAM --> RECORDER
    
    RECORDER --> RULES
    RULES --> EVAL
    
    EVAL --> S3BUCKET
    EVAL --> DASHBOARD
    EVAL -.Non-Compliant.-> SNS
    
    SNS --> SSM
    SNS --> LAMBDA
    
    SSM -.Fix.-> S3
    SSM -.Fix.-> EC2
    LAMBDA -.Fix.-> RDS

    style RECORDER fill:#e1f5fe
    style RULES fill:#fff3e0
    style EVAL fill:#fff3e0
    style S3BUCKET fill:#c8e6c9
    style DASHBOARD fill:#c8e6c9
    style SNS fill:#ffebee

See: diagrams/07_domain6_config_compliance.mmd

Diagram Explanation (Detailed):
The AWS Config compliance monitoring diagram shows how continuous compliance works. AWS resources (S3, EC2, RDS, IAM) are monitored by the Config Recorder (blue), which tracks all configuration changes in real-time. The Config Rules (orange) define desired configurations - these can be AWS-managed rules or custom rules. The Compliance Evaluation Engine (orange) evaluates resources against rules whenever changes occur or on a periodic schedule. Evaluation results are stored in an S3 bucket (green) as configuration history and displayed in the Config Dashboard (green) for visibility. When resources are found non-compliant, Config sends notifications to an SNS topic (red). The SNS topic triggers remediation actions through Systems Manager Automation (for AWS-managed remediation) or Lambda functions (for custom remediation). Remediation automatically fixes non-compliant resources, bringing them back into compliance. This creates a continuous compliance loop: monitor → evaluate → alert → remediate → monitor.

Detailed Example 1: Enforcing S3 Bucket Encryption
Your security policy requires all S3 buckets to have encryption enabled. You create a Config rule using the AWS-managed rule s3-bucket-server-side-encryption-enabled. Config evaluates all existing S3 buckets and finds 5 buckets without encryption - marking them as non-compliant. You configure automatic remediation using the Systems Manager Automation document AWS-EnableS3BucketEncryption. When Config detects a non-compliant bucket, it triggers the automation document, which enables default encryption (SSE-S3) on the bucket. The bucket becomes compliant. Going forward, if someone creates a new S3 bucket without encryption, Config detects it within minutes, marks it non-compliant, and automatically enables encryption. You also configure an SNS notification to alert the security team when non-compliant buckets are found. This provides both automated remediation and human oversight.

Detailed Example 2: Multi-Account Compliance with Config Aggregator
Your organization has 50 AWS accounts and needs centralized compliance visibility. You designate a Security account as the Config aggregator account. You create a Config aggregator that collects compliance data from all 50 accounts. In each member account, you authorize the aggregator account to collect data. Now, from the Security account, you can view compliance status across all accounts in a single dashboard. You create organization-wide Config rules that apply to all accounts: "Require MFA for root users", "Require encrypted EBS volumes", "Disallow public S3 buckets". These rules are evaluated in each account, and results are aggregated. The security team can see that 45 accounts are fully compliant, 3 have non-compliant S3 buckets, and 2 have root users without MFA. They can drill down into specific accounts and resources to investigate. This centralized view eliminates the need to check each account individually.

Detailed Example 3: Custom Config Rule for Approved AMIs
Your organization has a security requirement that EC2 instances must use approved AMIs from a whitelist. AWS doesn't have a managed rule for this, so you create a custom Config rule. You write a Lambda function that receives EC2 instance configurations from Config. The function checks if the instance's AMI ID is in the approved list (stored in Parameter Store). If the AMI is approved, the function returns "COMPLIANT". If not, it returns "NON_COMPLIANT" with a message. You create a Config rule that invokes this Lambda function whenever an EC2 instance is launched or modified. When a developer launches an instance with an unapproved AMI, Config marks it non-compliant within minutes. You configure remediation to send an SNS notification to the developer and security team. The security team investigates and either approves the AMI (adding it to the whitelist) or terminates the instance. This custom rule enforces your organization-specific security policy.

Must Know (Critical Facts):

  • Config recorder must be enabled in each region - Config is region-specific
  • Configuration items (CIs) contain resource configuration, relationships, and change history
  • Config rules are evaluated on change (change-triggered) or schedule (periodic)
  • Automatic remediation uses Systems Manager Automation documents
  • Config aggregator provides multi-account, multi-region compliance view
  • Conformance packs are collections of Config rules for compliance frameworks (CIS, PCI-DSS)
  • Config charges per configuration item recorded and per rule evaluation

When to use (Comprehensive):

  • ✅ Use Config when: You need continuous compliance monitoring of AWS resources
  • ✅ Use Config when: You need configuration change history for troubleshooting or forensics
  • ✅ Use Config rules when: You want to enforce security policies automatically
  • ✅ Use Config aggregator when: You need centralized compliance view across multiple accounts
  • ✅ Use conformance packs when: You need to comply with specific frameworks (CIS, PCI-DSS)
  • ❌ Don't use Config when: You only need point-in-time compliance checks - use manual audits
  • ❌ Don't use Config when: You need real-time enforcement - use SCPs or IAM policies instead

Limitations & Constraints:

  • Config is region-specific - must enable in each region separately
  • Maximum 150 Config rules per region (can request increase)
  • Custom Config rules limited by Lambda timeout (15 minutes)
  • Configuration items retained for 7 years in S3
  • Some resource types not supported by Config - check documentation

💡 Tips for Understanding:

  • Think of Config as "continuous configuration auditing" - always watching, always checking
  • Config rules = desired state, Compliance evaluation = actual state vs desired state
  • Remediation = automatic fixing of non-compliant resources
  • Aggregator = centralized view across accounts and regions

⚠️ Common Mistakes & Misconceptions:

  • Mistake 1: Thinking Config prevents non-compliant actions
    • Why it's wrong: Config is detective, not preventive - it detects violations after they occur
    • Correct understanding: Config evaluates resources after changes are made. For prevention, use SCPs or IAM policies. Config is for detection and remediation, not prevention
  • Mistake 2: Assuming Config is enabled by default
    • Why it's wrong: Config must be explicitly enabled in each region and account
    • Correct understanding: Config is opt-in. You must enable the Config recorder, specify resource types to track, and create rules. Control Tower enables Config automatically
  • Mistake 3: Forgetting that Config is region-specific
    • Why it's wrong: Enabling Config in us-east-1 doesn't monitor resources in us-west-2
    • Correct understanding: Config operates per region. Enable Config in all regions where you have resources. Use Config aggregator for multi-region view

🔗 Connections to Other Topics:

  • Relates to CloudTrail because: Config tracks "what" changed, CloudTrail tracks "who" changed it
  • Builds on Systems Manager by: Using Automation documents for remediation
  • Often used with Security Hub to: Aggregate compliance findings across services
  • Integrates with Organizations to: Deploy organization-wide Config rules

Troubleshooting Common Issues:

  • Issue 1: Config rules showing "No resources in scope"
    • Solution: Verify Config recorder is enabled and recording the resource types referenced by the rule. Check that resources exist in the region where Config is enabled
  • Issue 2: Automatic remediation not triggering
    • Solution: Check IAM role for Config has permissions to invoke Systems Manager Automation. Verify remediation action is configured correctly on the Config rule
  • Issue 3: Config aggregator not showing data from member accounts
    • Solution: Verify member accounts have authorized the aggregator account. Check that Config is enabled in member accounts and recording data

Chapter Summary

What We Covered

  • AWS Organizations: Multi-account management, SCPs for guardrails, consolidated billing
  • Control Tower: Automated landing zone setup, Account Factory, guardrails, drift detection
  • AWS Config: Continuous compliance monitoring, Config rules, automatic remediation
  • Compliance Frameworks: Conformance packs, Config aggregator, multi-account compliance

Critical Takeaways

  1. Organizations: Centralized management of multiple accounts. SCPs define maximum permissions and cannot be bypassed by IAM.
  2. SCPs: Filter IAM permissions but don't grant them. Deny always wins. Management account exempt from SCPs.
  3. Control Tower: Automates secure multi-account setup. Creates Log Archive and Audit accounts. Provides guardrails and Account Factory.
  4. Guardrails: Preventive (SCPs) prevent actions. Detective (Config rules) detect violations. Mandatory guardrails always enforced.
  5. Config: Continuously monitors resource configurations. Evaluates against rules. Provides configuration history and change tracking.
  6. Config Rules: AWS-managed (pre-built) or custom (Lambda). Evaluated on change or schedule. Can trigger automatic remediation.
  7. Config Aggregator: Centralized compliance view across multiple accounts and regions. Requires authorization from member accounts.

Self-Assessment Checklist

Test yourself before moving on:

  • I understand the difference between SCPs and IAM policies
  • I can explain why the management account is exempt from SCPs
  • I know the two core accounts created by Control Tower
  • I understand the difference between preventive and detective guardrails
  • I can describe how Config evaluates compliance
  • I know when to use Config vs SCPs for enforcement
  • I understand how Config aggregator provides multi-account visibility

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (Organizations and Control Tower)
  • Domain 6 Bundle 2: Questions 26-50 (Config and Compliance)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review sections: SCP evaluation logic, Control Tower guardrails, Config rule types
  • Focus on: When to use SCPs vs IAM, Control Tower use cases, Config remediation

Quick Reference Card

Key Services:

  • Organizations: Multi-account management, SCPs, consolidated billing
  • Control Tower: Automated landing zone, Account Factory, guardrails
  • Config: Continuous compliance monitoring, configuration history
  • Service Catalog: Account Factory, approved service portfolios

Key Concepts:

  • SCP: Maximum permissions for accounts, filters IAM policies
  • Guardrails: Preventive (SCPs) or detective (Config rules)
  • Landing Zone: Multi-account environment created by Control Tower
  • Config Rule: Desired configuration, evaluated against actual state
  • Conformance Pack: Collection of Config rules for compliance framework

Decision Points:

  • Need to prevent actions across accounts? → Use SCPs
  • Need to detect violations after they occur? → Use Config rules
  • Need automated account provisioning? → Use Control Tower Account Factory
  • Need multi-account compliance view? → Use Config aggregator
  • Need to enforce encryption organization-wide? → Use SCP to deny unencrypted operations

Common Exam Traps:

  • ❌ SCPs grant permissions → FALSE (they only filter/restrict)
  • ❌ SCPs apply to management account → FALSE (management account exempt)
  • ❌ Config prevents non-compliant actions → FALSE (Config is detective, not preventive)
  • ❌ Control Tower can be enabled on any existing Organizations → FALSE (requires specific structure)
  • ❌ Config is enabled by default → FALSE (must be explicitly enabled per region)


Section 4: Advanced Governance - CloudFormation, Service Catalog, and Firewall Manager

Introduction

The problem: As AWS environments grow, maintaining consistent security configurations becomes challenging. Manual deployments lead to configuration drift, security gaps, and compliance violations. Without standardized deployment processes and centralized policy management, organizations struggle to maintain security at scale.

The solution: AWS provides services for infrastructure as code (CloudFormation), approved service portfolios (Service Catalog), and centralized firewall management (Firewall Manager). Together, these services enable consistent, secure deployments across accounts and regions.

Why it's tested: The exam tests your ability to implement secure deployment strategies, enforce standards through Service Catalog, and manage security policies centrally with Firewall Manager.

Core Concepts

AWS CloudFormation - Infrastructure as Code Security

What it is: AWS CloudFormation enables you to define AWS infrastructure as code using templates. From a security perspective, CloudFormation ensures consistent, repeatable deployments with built-in security controls.

Why it exists: Manual infrastructure deployment is error-prone and inconsistent. CloudFormation templates can be version-controlled, reviewed, and tested before deployment, ensuring security standards are met.

Real-world analogy: CloudFormation is like architectural blueprints for a building. Just as blueprints ensure every building follows safety codes and design standards, CloudFormation templates ensure every deployment follows security standards.

How it works (Detailed step-by-step):

  1. Template Creation: You define infrastructure in a CloudFormation template (JSON or YAML).
  2. Security Review: Security teams review templates for compliance with security standards.
  3. Template Hardening: You apply security best practices: encryption enabled, public access blocked, least privilege IAM roles.
  4. Stack Creation: You create a CloudFormation stack from the template.
  5. Resource Provisioning: CloudFormation provisions resources according to the template.
  6. Drift Detection: CloudFormation detects if resources are modified outside of CloudFormation.
  7. Stack Updates: You update stacks by modifying templates, ensuring changes are tracked and reviewed.

📊 CloudFormation Drift Detection Diagram:

graph TB
    Template[CloudFormation Template<br/>Desired State]
    Stack[CloudFormation Stack<br/>Deployed Resources]
    
    subgraph "Deployed Resources"
        S3[S3 Bucket<br/>Encryption: Enabled]
        EC2[EC2 Instance<br/>Type: t3.medium]
        IAM[IAM Role<br/>Policy: ReadOnly]
    end
    
    Manual[Manual Change<br/>Outside CloudFormation]
    
    subgraph "Drift Detection"
        Detect[Detect Drift<br/>Compare Template vs Actual]
        Report[Drift Report<br/>S3: No Drift<br/>EC2: DRIFTED (t3.large)<br/>IAM: No Drift]
    end
    
    Template --> Stack
    Stack --> S3
    Stack --> EC2
    Stack --> IAM
    
    Manual -.->|Changed instance type| EC2
    
    Stack --> Detect
    Detect --> Report
    
    style Report fill:#ffebee
    style EC2 fill:#ffebee
    style S3 fill:#c8e6c9
    style IAM fill:#c8e6c9

See: diagrams/07_domain6_cloudformation_drift_detection.mmd

Diagram Explanation (Detailed):

The diagram shows CloudFormation drift detection identifying unauthorized changes. A CloudFormation template defines the desired state: S3 bucket with encryption enabled, EC2 instance type t3.medium, and IAM role with read-only policy. CloudFormation creates a stack and provisions these resources. Later, someone manually changes the EC2 instance type to t3.large outside of CloudFormation (bypassing the template). When drift detection runs, CloudFormation compares the actual resource configurations with the template. The drift report shows: S3 bucket has no drift (encryption still enabled), EC2 instance has drifted (type changed from t3.medium to t3.large), and IAM role has no drift (policy unchanged). This identifies the unauthorized change, allowing the security team to investigate and remediate. Drift detection ensures resources remain compliant with approved templates.

Detailed Example 1: Hardening CloudFormation Templates

A company wants to ensure all S3 buckets created via CloudFormation have encryption and block public access. Here's how they harden templates: (1) They create a CloudFormation template for S3 buckets with security controls:

Resources:
  SecureBucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketEncryption:
        ServerSideEncryptionConfiguration:
          - ServerSideEncryptionByDefault:
              SSEAlgorithm: AES256
      PublicAccessBlockConfiguration:
        BlockPublicAcls: true
        BlockPublicPolicy: true
        IgnorePublicAcls: true
        RestrictPublicBuckets: true
      VersioningConfiguration:
        Status: Enabled
      LoggingConfiguration:
        DestinationBucketName: !Ref LoggingBucket
        LogFilePrefix: access-logs/

(2) They require all S3 buckets to be created using this template. (3) A developer creates a stack from the template. (4) The S3 bucket is created with encryption, public access blocking, versioning, and logging enabled by default. (5) The company achieves consistent security across all S3 buckets. CloudFormation templates enforced security standards.

Detailed Example 2: Using CloudFormation StackSets for Multi-Account Deployment

A company wants to deploy security baselines to 50 AWS accounts. Here's how they use StackSets: (1) They create a CloudFormation template with security baselines: CloudTrail enabled, Config enabled, GuardDuty enabled, Security Hub enabled. (2) They create a StackSet from the template. (3) They specify target accounts (all 50 accounts) and regions (us-east-1, us-west-2). (4) CloudFormation deploys the stack to all 50 accounts simultaneously. (5) Within 30 minutes, all accounts have the security baseline deployed. (6) When they need to update the baseline (e.g., enable a new Config rule), they update the StackSet. (7) The update is automatically deployed to all 50 accounts. StackSets enabled centralized, consistent security deployments across accounts.

Detailed Example 3: Detecting and Remediating Configuration Drift

A company uses CloudFormation to deploy infrastructure. Here's how they detect drift: (1) They deploy an EC2 instance with CloudFormation, specifying instance type t3.medium and security group sg-12345. (2) A developer manually changes the instance type to t3.large to troubleshoot a performance issue. (3) The security team runs drift detection on the CloudFormation stack. (4) CloudFormation reports drift: instance type changed from t3.medium to t3.large. (5) The team investigates and finds the manual change was unauthorized. (6) They update the stack to restore the instance to t3.medium. (7) They implement a Config rule to alert on manual changes to CloudFormation-managed resources. Drift detection identified unauthorized changes, maintaining infrastructure compliance.

Must Know (Critical Facts):

  • CloudFormation templates should be version-controlled and reviewed before deployment
  • Drift detection identifies resources modified outside of CloudFormation
  • StackSets enable deploying stacks to multiple accounts and regions simultaneously
  • CloudFormation supports rollback on failure to prevent partial deployments
  • CloudFormation change sets allow previewing changes before applying them
  • CloudFormation can create IAM roles with least privilege for resource provisioning
  • CloudFormation templates can be scanned for security issues using tools like cfn-nag

When to use (Comprehensive):

  • ✅ Use when: You need consistent, repeatable infrastructure deployments
  • ✅ Use when: You want to enforce security standards through templates
  • ✅ Use when: You need to deploy infrastructure to multiple accounts (StackSets)
  • ✅ Use when: You want to detect unauthorized configuration changes (drift detection)
  • ✅ Use when: Compliance requires infrastructure as code
  • ❌ Don't use when: You have simple, one-off deployments (manual creation is faster)
  • ❌ Don't use when: Your infrastructure changes frequently and unpredictably

AWS Service Catalog - Approved Service Portfolios

What it is: AWS Service Catalog enables you to create and manage catalogs of approved AWS services and configurations. Users can launch pre-approved products without needing deep AWS knowledge or broad IAM permissions.

Why it exists: Allowing users to create any AWS resource with full permissions creates security risks. Service Catalog provides self-service access to approved, secure configurations while maintaining governance.

Real-world analogy: Service Catalog is like a company's approved vendor list. Employees can order from approved vendors without needing approval for each purchase, but they can't order from unapproved vendors.

How it works (Detailed step-by-step):

  1. Product Creation: Administrators create products (CloudFormation templates) with approved configurations.
  2. Portfolio Creation: Administrators group products into portfolios (e.g., "Development Resources").
  3. Access Grants: Administrators grant IAM users/roles access to portfolios.
  4. Product Launch: Users browse the catalog and launch approved products.
  5. Provisioning: Service Catalog provisions resources using CloudFormation with a service role.
  6. Governance: Administrators maintain control over what can be deployed and how.

📊 Service Catalog Portfolio Diagram:

graph TB
    subgraph "Service Catalog"
        Portfolio[Portfolio: Development Resources]
        
        subgraph "Products"
            Prod1[Product: Secure S3 Bucket<br/>Template: s3-secure.yaml]
            Prod2[Product: Web Server<br/>Template: ec2-web.yaml]
            Prod3[Product: Database<br/>Template: rds-mysql.yaml]
        end
        
        Constraints[Launch Constraints<br/>- Service Role: SC-LaunchRole<br/>- Allowed Regions: us-east-1<br/>- Required Tags: Project, Owner]
    end
    
    subgraph "Users"
        Dev1[Developer 1<br/>IAM User]
        Dev2[Developer 2<br/>IAM User]
    end
    
    subgraph "Provisioned Resources"
        S3[S3 Bucket<br/>Encryption: Enabled<br/>Public Access: Blocked]
        EC2[EC2 Instance<br/>Security Group: Restricted<br/>IAM Role: Least Privilege]
    end
    
    Portfolio --> Prod1
    Portfolio --> Prod2
    Portfolio --> Prod3
    Portfolio --> Constraints
    
    Dev1 -->|Browse & Launch| Portfolio
    Dev2 -->|Browse & Launch| Portfolio
    
    Prod1 -.->|Provision| S3
    Prod2 -.->|Provision| EC2
    
    style Portfolio fill:#c8e6c9
    style S3 fill:#e1f5fe
    style EC2 fill:#e1f5fe

See: diagrams/07_domain6_service_catalog_portfolio.mmd

Diagram Explanation (Detailed):

The diagram shows AWS Service Catalog enabling self-service access to approved resources. Administrators create a portfolio called "Development Resources" containing three products: Secure S3 Bucket, Web Server, and Database. Each product is backed by a CloudFormation template with security controls built-in. Launch constraints are applied to the portfolio: resources must be provisioned using a specific service role (SC-LaunchRole) with least privilege permissions, resources can only be created in us-east-1, and all resources must be tagged with Project and Owner. Developers (Dev1 and Dev2) are granted access to the portfolio. They can browse available products and launch them without needing broad IAM permissions. When Dev1 launches the Secure S3 Bucket product, Service Catalog provisions an S3 bucket using the template, which includes encryption enabled and public access blocked. When Dev2 launches the Web Server product, Service Catalog provisions an EC2 instance with a restricted security group and least privilege IAM role. Developers get self-service access to approved resources, while administrators maintain governance through templates and constraints.

Detailed Example 1: Enabling Self-Service with Governance

A company wants to allow developers to create S3 buckets without granting them s3:CreateBucket permissions. Here's how they use Service Catalog: (1) They create a CloudFormation template for a secure S3 bucket (encryption, versioning, logging enabled). (2) They create a Service Catalog product from the template. (3) They create a portfolio and add the product. (4) They create a launch constraint with a service role that has s3:CreateBucket permissions. (5) They grant developers access to the portfolio (no direct S3 permissions needed). (6) A developer browses the catalog and launches the S3 bucket product. (7) Service Catalog uses the service role to create the bucket. (8) The bucket is created with all security controls from the template. (9) The developer has a secure S3 bucket without needing broad IAM permissions. Service Catalog enabled self-service while maintaining governance.

Detailed Example 2: Enforcing Tagging with Service Catalog

A company requires all resources to be tagged with Project and Owner. Here's how they enforce this with Service Catalog: (1) They create Service Catalog products with CloudFormation templates that include tag parameters. (2) They create a launch constraint requiring Project and Owner tags. (3) When a developer launches a product, they must provide values for Project and Owner. (4) Service Catalog provisions the resource with the required tags. (5) Resources created through Service Catalog are automatically compliant with tagging requirements. (6) The company can track resource ownership and project allocation. Service Catalog enforced tagging standards.

Detailed Example 3: Multi-Account Product Distribution

A company wants to provide approved products to 50 AWS accounts. Here's how they use Service Catalog: (1) They create products in a central "Catalog" account. (2) They share the portfolio with all 50 accounts using AWS Organizations. (3) Developers in all 50 accounts can browse and launch products from the shared portfolio. (4) Products are provisioned in each account using local service roles. (5) The central team maintains a single source of truth for approved products. (6) When they update a product, all accounts automatically see the new version. Service Catalog enabled centralized product management across accounts.

Must Know (Critical Facts):

  • Service Catalog products are backed by CloudFormation templates
  • Launch constraints specify the IAM role used to provision resources
  • Users don't need permissions to create resources - the service role has permissions
  • Service Catalog can enforce tagging, region restrictions, and other constraints
  • Portfolios can be shared across accounts using AWS Organizations
  • Service Catalog provides self-service access while maintaining governance
  • Service Catalog integrates with AWS Organizations for multi-account distribution

When to use (Comprehensive):

  • ✅ Use when: You want to provide self-service access to approved resources
  • ✅ Use when: You need to enforce security standards through approved templates
  • ✅ Use when: You want to limit what users can deploy without broad IAM permissions
  • ✅ Use when: You need to enforce tagging, region restrictions, or other constraints
  • ✅ Use when: You want to centrally manage approved products across accounts
  • ❌ Don't use when: Users need full flexibility to create any resource
  • ❌ Don't use when: You have a small team with centralized infrastructure management

AWS Firewall Manager - Centralized Firewall Policy Management

What it is: AWS Firewall Manager is a security management service that enables you to centrally configure and manage firewall rules across accounts and applications in AWS Organizations.

Why it exists: Managing WAF rules, Shield protections, and security group rules individually in each account is impractical. Firewall Manager provides centralized policy management and automatic enforcement.

Real-world analogy: Firewall Manager is like a corporate security policy that applies to all office buildings. Instead of each building having different security rules, the corporate policy ensures consistent security across all locations.

How it works (Detailed step-by-step):

  1. Policy Creation: You create a Firewall Manager policy specifying security rules (WAF, Shield, Security Groups, Network Firewall).
  2. Scope Definition: You specify which accounts and resources the policy applies to (using tags or resource types).
  3. Automatic Application: Firewall Manager automatically applies the policy to all in-scope resources.
  4. Compliance Monitoring: Firewall Manager continuously monitors compliance and reports non-compliant resources.
  5. Automatic Remediation: Firewall Manager can automatically remediate non-compliant resources.
  6. New Resource Protection: When new resources are created, Firewall Manager automatically applies policies.

📊 Firewall Manager Policies Diagram:

graph TB
    subgraph "AWS Organizations"
        Mgmt[Management Account<br/>Firewall Manager Admin]
        
        subgraph "Accounts"
            Acc1[Account 1<br/>Production]
            Acc2[Account 2<br/>Development]
            Acc3[Account 3<br/>Staging]
        end
    end
    
    subgraph "Firewall Manager Policies"
        WAF_Policy[WAF Policy<br/>OWASP Top 10 Rules<br/>Scope: All ALBs]
        Shield_Policy[Shield Advanced Policy<br/>DDoS Protection<br/>Scope: All CloudFront]
        SG_Policy[Security Group Policy<br/>Block SSH from Internet<br/>Scope: All EC2]
    end
    
    subgraph "Resources"
        ALB1[ALB in Acc1<br/>WAF: Applied]
        ALB2[ALB in Acc2<br/>WAF: Applied]
        CF1[CloudFront in Acc1<br/>Shield: Applied]
        EC2_1[EC2 in Acc3<br/>SG: Compliant]
    end
    
    Mgmt --> WAF_Policy
    Mgmt --> Shield_Policy
    Mgmt --> SG_Policy
    
    WAF_Policy -.->|Auto-Apply| ALB1
    WAF_Policy -.->|Auto-Apply| ALB2
    Shield_Policy -.->|Auto-Apply| CF1
    SG_Policy -.->|Monitor & Remediate| EC2_1
    
    Compliance[Compliance Dashboard<br/>All Resources: Compliant]
    
    WAF_Policy --> Compliance
    Shield_Policy --> Compliance
    SG_Policy --> Compliance
    
    style Compliance fill:#c8e6c9
    style WAF_Policy fill:#e1f5fe
    style Shield_Policy fill:#fff3e0
    style SG_Policy fill:#f3e5f5

See: diagrams/07_domain6_firewall_manager_policies.mmd

Diagram Explanation (Detailed):

The diagram shows Firewall Manager providing centralized policy management across multiple accounts. The management account is designated as the Firewall Manager administrator. Three policies are created: (1) WAF Policy applies OWASP Top 10 rules to all Application Load Balancers across all accounts. (2) Shield Advanced Policy enables DDoS protection for all CloudFront distributions. (3) Security Group Policy monitors and remediates security groups that allow SSH from the internet on EC2 instances. Firewall Manager automatically applies these policies to in-scope resources: ALBs in Account 1 and Account 2 automatically get WAF rules applied, CloudFront in Account 1 automatically gets Shield Advanced protection, and EC2 instances in Account 3 are monitored for security group compliance. When a new ALB is created in any account, Firewall Manager automatically applies the WAF policy. The compliance dashboard shows all resources are compliant with policies. Firewall Manager provides centralized, automated policy enforcement across the organization.

Detailed Example 1: Enforcing WAF Rules Across All ALBs

A company wants to ensure all Application Load Balancers have WAF protection. Here's how they use Firewall Manager: (1) They designate the security account as the Firewall Manager administrator. (2) They create a Firewall Manager WAF policy with AWS Managed Rules for OWASP Top 10. (3) They set the policy scope to "All Application Load Balancers" across all accounts. (4) Firewall Manager automatically creates Web ACLs and associates them with all existing ALBs. (5) A developer creates a new ALB in the development account. (6) Within minutes, Firewall Manager automatically associates a Web ACL with the new ALB. (7) The ALB is protected by WAF rules without manual configuration. (8) The compliance dashboard shows all ALBs are protected. Firewall Manager automated WAF deployment across all accounts.

Detailed Example 2: Remediating Non-Compliant Security Groups

A company wants to ensure no security groups allow SSH from the internet. Here's how they use Firewall Manager: (1) They create a Firewall Manager security group policy that identifies security groups allowing SSH (port 22) from 0.0.0.0/0. (2) They set the policy to "Auto-remediate" non-compliant security groups. (3) Firewall Manager scans all security groups and finds 10 that allow SSH from the internet. (4) Firewall Manager automatically removes the rule allowing SSH from 0.0.0.0/0. (5) The security groups are now compliant. (6) A developer accidentally creates a security group allowing SSH from the internet. (7) Firewall Manager detects the non-compliant security group within minutes. (8) Firewall Manager automatically remediates by removing the rule. Firewall Manager continuously enforced security group policies.

Must Know (Critical Facts):

  • Firewall Manager requires AWS Organizations and a designated administrator account
  • Firewall Manager supports WAF, Shield Advanced, Security Groups, Network Firewall, and DNS Firewall policies
  • Policies can be scoped by account, organizational unit, resource type, or tags
  • Firewall Manager can automatically remediate non-compliant resources
  • Firewall Manager automatically applies policies to new resources
  • Firewall Manager provides centralized compliance reporting
  • Firewall Manager policies are inherited by new accounts added to the organization

When to use (Comprehensive):

  • ✅ Use when: You need to enforce firewall policies across multiple accounts
  • ✅ Use when: You want automatic policy application to new resources
  • ✅ Use when: You need centralized compliance reporting for firewall rules
  • ✅ Use when: You want to automatically remediate non-compliant resources
  • ✅ Use when: You have AWS Organizations with multiple accounts
  • ❌ Don't use when: You have a single AWS account (use individual services instead)
  • ❌ Don't use when: You need highly customized, per-resource firewall rules

Section 5: Data Governance and Backup Compliance

Introduction

The problem: Data protection and backup compliance are critical governance requirements. Organizations must ensure data is backed up regularly, backups are encrypted, and backup retention meets compliance requirements. Without centralized backup management, ensuring compliance across all resources is challenging.

The solution: AWS Backup provides centralized backup management with policy-based backup plans, encryption, and compliance reporting. AWS Backup Vault Lock ensures backups cannot be deleted, meeting regulatory requirements for immutable backups.

Why it's tested: The exam tests your ability to implement compliant backup strategies, enforce backup policies, and ensure data protection meets regulatory requirements.

Core Concepts

AWS Backup - Centralized Backup Management

What it is: AWS Backup is a fully managed backup service that centralizes and automates data protection across AWS services. It provides policy-based backup plans, encryption, and compliance reporting.

Why it exists: Managing backups individually for each service (EBS snapshots, RDS snapshots, DynamoDB backups) is complex and error-prone. AWS Backup provides a single place to manage all backups with consistent policies.

Real-world analogy: AWS Backup is like a centralized backup system for a company's data. Instead of each department managing their own backups differently, the company has a single backup policy that applies to all data.

How it works (Detailed step-by-step):

  1. Backup Plan Creation: You create a backup plan defining backup frequency, retention, and lifecycle rules.
  2. Resource Assignment: You assign resources to the backup plan using tags or resource IDs.
  3. Backup Vault: You create a backup vault to store backups (encrypted with KMS).
  4. Automated Backups: AWS Backup automatically creates backups according to the plan.
  5. Lifecycle Management: AWS Backup transitions backups to cold storage and deletes them based on retention rules.
  6. Compliance Reporting: AWS Backup provides reports showing backup compliance.
  7. Cross-Region Copy: AWS Backup can copy backups to other regions for disaster recovery.

📊 AWS Backup Vault Lock Diagram:

graph TB
    subgraph "Backup Plan"
        Plan[Backup Plan<br/>Daily at 2 AM<br/>Retain 30 days<br/>Cold storage after 7 days]
        Resources[Resources<br/>Tag: Backup=Daily]
    end
    
    subgraph "Backup Vault"
        Vault[Backup Vault<br/>Encrypted with KMS]
        Lock[Vault Lock<br/>Compliance Mode<br/>Min Retention: 30 days<br/>Max Retention: 365 days]
    end
    
    subgraph "Backups"
        Backup1[Backup 1<br/>Day 1<br/>Warm Storage]
        Backup2[Backup 2<br/>Day 8<br/>Cold Storage]
        Backup3[Backup 3<br/>Day 30<br/>Deleted]
    end
    
    Plan --> Resources
    Resources -.->|Auto Backup| Vault
    Vault --> Lock
    
    Vault --> Backup1
    Vault --> Backup2
    Vault --> Backup3
    
    Delete[Attempt to Delete<br/>Backup 1]
    Delete -.->|❌ Denied by Vault Lock| Backup1
    
    style Lock fill:#c8e6c9
    style Delete fill:#ffebee
    style Backup1 fill:#e1f5fe
    style Backup2 fill:#fff3e0

See: diagrams/07_domain6_aws_backup_vault_lock.mmd

Diagram Explanation (Detailed):

The diagram shows AWS Backup with Vault Lock ensuring immutable backups. A backup plan is created with daily backups at 2 AM, 30-day retention, and transition to cold storage after 7 days. Resources tagged with "Backup=Daily" are automatically backed up according to the plan. Backups are stored in a backup vault encrypted with a KMS key. Vault Lock is enabled in compliance mode with minimum retention of 30 days and maximum retention of 365 days. Three backups are shown: Backup 1 (Day 1) is in warm storage, Backup 2 (Day 8) has been transitioned to cold storage, and Backup 3 (Day 30) is deleted after retention expires. When someone attempts to delete Backup 1 before 30 days, Vault Lock denies the deletion, ensuring backups are immutable. This meets regulatory requirements for backup retention and prevents accidental or malicious deletion. AWS Backup with Vault Lock provides compliant, immutable backups.

Detailed Example 1: Implementing Organization-Wide Backup Policy

A company wants to ensure all production resources are backed up daily. Here's how they use AWS Backup: (1) They create a backup plan: daily backups at 2 AM, retain for 30 days, transition to cold storage after 7 days. (2) They tag all production resources with "Environment=Production". (3) They assign resources with "Environment=Production" tag to the backup plan. (4) AWS Backup automatically discovers all tagged resources (EC2, RDS, DynamoDB, EFS, etc.). (5) Backups are created daily for all production resources. (6) After 7 days, backups are transitioned to cold storage (lower cost). (7) After 30 days, backups are automatically deleted. (8) The compliance dashboard shows 100% of production resources are backed up. AWS Backup automated backup compliance across all services.

Detailed Example 2: Cross-Region Backup for Disaster Recovery

A company wants to ensure backups are available in another region for disaster recovery. Here's how they use AWS Backup: (1) They create a backup plan with cross-region copy enabled. (2) They specify the destination region (us-west-2) and retention (90 days). (3) AWS Backup creates backups in the primary region (us-east-1). (4) AWS Backup automatically copies backups to us-west-2. (5) If us-east-1 experiences a regional outage, backups in us-west-2 are available for recovery. (6) The company can restore resources in us-west-2 from the copied backups. AWS Backup enabled cross-region disaster recovery.

Detailed Example 3: Enforcing Immutable Backups with Vault Lock

A financial services company must comply with regulations requiring immutable backups. Here's how they use Vault Lock: (1) They create a backup vault for compliance backups. (2) They enable Vault Lock in compliance mode with minimum retention of 90 days. (3) They create a backup plan that stores backups in the locked vault. (4) Backups are created and stored in the vault. (5) An administrator attempts to delete a backup to free up storage. (6) Vault Lock denies the deletion because the backup hasn't reached the minimum retention period. (7) After 90 days, the backup can be deleted. (8) The company meets regulatory requirements for immutable backups. Vault Lock ensured backups cannot be deleted prematurely.

Must Know (Critical Facts):

  • AWS Backup supports EC2, EBS, RDS, DynamoDB, EFS, FSx, Storage Gateway, and more
  • Backup plans define backup frequency, retention, and lifecycle rules
  • Backup vaults store backups and can be encrypted with KMS keys
  • Vault Lock ensures backups are immutable (cannot be deleted before retention expires)
  • Vault Lock has two modes: governance (can be overridden) and compliance (cannot be overridden)
  • AWS Backup can copy backups to other regions for disaster recovery
  • AWS Backup provides compliance reporting showing backup coverage

When to use (Comprehensive):

  • ✅ Use when: You need centralized backup management across multiple services
  • ✅ Use when: Compliance requires regular backups with specific retention periods
  • ✅ Use when: You need immutable backups (Vault Lock)
  • ✅ Use when: You want automated backup lifecycle management (cold storage, deletion)
  • ✅ Use when: You need cross-region backup copies for disaster recovery
  • ✅ Use when: You want compliance reporting for backup coverage
  • ❌ Don't use when: You have simple backup needs for a single service (use service-native backups)
  • ❌ Don't use when: You need real-time replication (use service-specific replication instead)

AWS Audit Manager - Automated Compliance Evidence Collection

What it is: AWS Audit Manager helps you continuously audit your AWS usage to simplify risk assessment and compliance with regulations and industry standards. It automates evidence collection and generates audit-ready reports.

Why it exists: Preparing for audits is time-consuming and requires collecting evidence from multiple sources. Audit Manager automates evidence collection and organizes it into audit-ready reports.

Real-world analogy: Audit Manager is like an automated compliance assistant that continuously collects evidence of your security controls and organizes it into reports for auditors.

How it works (Detailed step-by-step):

  1. Framework Selection: You select a compliance framework (PCI-DSS, HIPAA, SOC 2, GDPR, etc.).
  2. Assessment Creation: You create an assessment based on the framework.
  3. Evidence Collection: Audit Manager automatically collects evidence from AWS services (CloudTrail, Config, Security Hub).
  4. Control Mapping: Evidence is mapped to specific controls in the framework.
  5. Manual Evidence: You can upload manual evidence (policies, procedures, screenshots).
  6. Assessment Report: Audit Manager generates an assessment report showing compliance status.
  7. Audit Preparation: The report is audit-ready and can be shared with auditors.

Detailed Example 1: Preparing for PCI-DSS Audit

A company processes credit card payments and must comply with PCI-DSS. Here's how they use Audit Manager: (1) They create an assessment using the PCI-DSS framework. (2) Audit Manager automatically collects evidence: CloudTrail logs showing access controls, Config rules showing encryption enabled, Security Hub findings showing vulnerability management. (3) Audit Manager maps evidence to PCI-DSS requirements (e.g., Requirement 10: Track and monitor all access to network resources). (4) The company uploads manual evidence: network diagrams, security policies, employee training records. (5) Audit Manager generates an assessment report showing compliance status for each requirement. (6) The company shares the report with their auditor. (7) The auditor reviews the evidence and confirms compliance. Audit Manager automated evidence collection, reducing audit preparation time from weeks to days.

Detailed Example 2: Continuous Compliance Monitoring

A company wants to continuously monitor compliance with SOC 2. Here's how they use Audit Manager: (1) They create an assessment using the SOC 2 framework. (2) Audit Manager continuously collects evidence as AWS resources are used. (3) The compliance dashboard shows real-time compliance status. (4) When a Config rule detects non-compliance (e.g., unencrypted S3 bucket), Audit Manager flags the control as non-compliant. (5) The security team remediates the issue. (6) Audit Manager automatically collects evidence of the remediation. (7) The control status is updated to compliant. Audit Manager provided continuous compliance monitoring.

Must Know (Critical Facts):

  • Audit Manager supports multiple compliance frameworks (PCI-DSS, HIPAA, SOC 2, GDPR, etc.)
  • Audit Manager automatically collects evidence from CloudTrail, Config, and Security Hub
  • Audit Manager can collect manual evidence (uploaded by users)
  • Audit Manager generates audit-ready reports
  • Audit Manager maps evidence to specific controls in compliance frameworks
  • Audit Manager provides continuous compliance monitoring

When to use (Comprehensive):

  • ✅ Use when: Preparing for compliance audits (PCI-DSS, HIPAA, SOC 2, etc.)
  • ✅ Use when: You need automated evidence collection
  • ✅ Use when: You want continuous compliance monitoring
  • ✅ Use when: You need audit-ready reports
  • ❌ Don't use when: You don't have compliance requirements
  • ❌ Don't use when: You have custom compliance frameworks not supported by Audit Manager

Chapter Summary

What We Covered

This chapter covered Domain 6: Management and Security Governance (14% of exam), including:

  • Multi-Account Management: AWS Organizations, Control Tower, SCPs, delegated administration
  • Deployment Strategy: CloudFormation, Service Catalog, tagging, Firewall Manager
  • Compliance: Config rules, Macie, Audit Manager, evidence collection
  • Security Gaps: Cost anomalies, unused resources, Well-Architected Tool
  • Resource Sharing: AWS RAM, cross-account sharing

Critical Takeaways

  1. AWS Organizations: Multi-account management, organizational units, SCPs
  2. Control Tower: Automated landing zone, guardrails, account factory
  3. SCPs: Service Control Policies, organization-wide permission limits
  4. Config: Configuration tracking, compliance rules, remediation
  5. Macie: Sensitive data discovery, PII detection, S3 scanning
  6. Audit Manager: Compliance frameworks, automated evidence collection
  7. CloudFormation: Infrastructure as code, drift detection, StackSets
  8. Service Catalog: Approved service portfolios, self-service provisioning
  9. Firewall Manager: Centralized firewall policy management
  10. Well-Architected Tool: Security pillar review, best practices

Self-Assessment Checklist

Test yourself before moving on:

  • I understand AWS Organizations and multi-account strategies
  • I know how to implement SCPs for guardrails
  • I can design a Control Tower landing zone
  • I understand Config rules and remediation
  • I know how to use Macie for data classification
  • I can design compliance monitoring with Audit Manager
  • I understand CloudFormation security best practices
  • I know how to use Service Catalog for governance
  • I can implement centralized firewall policies
  • I understand the Well-Architected Framework security pillar

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (Multi-account and Deployment)
  • Domain 6 Bundle 2: Questions 26-50 (Compliance and Governance)
  • Compliance & Governance Bundle: Questions 1-50
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review sections: SCPs, Config rules, Audit Manager, CloudFormation
  • Focus on: Multi-account strategies, compliance automation, governance

Quick Reference Card

Key Services:

  • Organizations: Multi-account management, SCPs, consolidated billing
  • Control Tower: Landing zone, guardrails, account factory
  • Config: Configuration tracking, compliance rules, remediation
  • Macie: Sensitive data discovery, PII detection
  • Audit Manager: Compliance frameworks, evidence collection
  • CloudFormation: Infrastructure as code, StackSets
  • Service Catalog: Approved service portfolios
  • Firewall Manager: Centralized firewall policies

Decision Points:

  • Need multi-account management? → Organizations
  • Need automated landing zone? → Control Tower
  • Need organization-wide guardrails? → SCPs
  • Need configuration compliance? → Config
  • Need sensitive data discovery? → Macie
  • Need compliance evidence? → Audit Manager
  • Need infrastructure as code? → CloudFormation
  • Need approved service catalog? → Service Catalog
  • Need centralized firewall management? → Firewall Manager

Best Practices:

  1. Use multi-account strategy (separate accounts for dev/test/prod)
  2. Implement SCPs for organization-wide guardrails
  3. Use Control Tower for automated account provisioning
  4. Enable Config rules for compliance monitoring
  5. Use Macie to discover sensitive data in S3
  6. Implement tagging strategy for resource management
  7. Use CloudFormation for consistent deployments
  8. Use Service Catalog for self-service provisioning
  9. Centralize security management with delegated administration
  10. Use Well-Architected Tool for security reviews

Chapter 6 Complete

Next Chapter: 08_integration - Integration and Advanced Topics


Chapter Summary

What We Covered

This chapter explored Management and Security Governance, the foundation of organizational security:

Centralized Account Management: Developing multi-account strategies with AWS Organizations, deploying AWS Control Tower for automated account provisioning, implementing Service Control Policies (SCPs) as guardrails, centralizing security management with delegated administration, and securing root account credentials.

Secure Deployment Strategy: Implementing Infrastructure as Code (IaC) with CloudFormation, enforcing tagging strategies, deploying approved services with Service Catalog, managing security policies with Firewall Manager, and sharing resources securely with AWS RAM.

Compliance Evaluation: Classifying data with Macie, assessing resource configurations with AWS Config rules, and collecting evidence with Security Hub and Audit Manager.

Security Gap Identification: Identifying cost and usage anomalies, finding unused resources with Trusted Advisor and Cost Explorer, using the Well-Architected Tool for security reviews, and reducing attack surfaces.

Critical Takeaways

  1. Multi-Account is Mandatory: Use AWS Organizations with multiple accounts for isolation (security account, logging account, production accounts, development accounts). Never run everything in a single account.

  2. SCPs are Guardrails: Service Control Policies don't grant permissions, they set boundaries. Use SCPs to prevent dangerous actions (disabling CloudTrail, leaving regions, deleting logs) across all accounts.

  3. Control Tower Automates Governance: AWS Control Tower automates account provisioning, applies guardrails (SCPs and Config rules), and centralizes logging. Use Account Factory for standardized account creation.

  4. Infrastructure as Code: Use CloudFormation for all infrastructure deployments. This ensures consistency, enables drift detection, and provides audit trails. Never make manual changes in production.

  5. Tagging is Critical: Implement organization-wide tagging strategies for cost allocation, access control (ABAC), and resource organization. Enforce tagging with SCPs and Config rules.

  6. Config for Compliance: Use AWS Config to continuously monitor resource configurations against compliance requirements. Create Config rules for security baselines (encryption enabled, public access blocked, etc.).

  7. Centralize Security: Use delegated administration to centralize security services (Security Hub, GuardDuty, Macie, Firewall Manager) in a dedicated security account. This provides organization-wide visibility.

  8. Automate Compliance: Use Audit Manager to automate evidence collection for compliance frameworks (PCI-DSS, HIPAA, SOC 2). This reduces manual audit work and ensures continuous compliance.

Self-Assessment Checklist

Test yourself before moving on:

  • I understand multi-account strategies and organizational unit (OU) design
  • I can deploy and configure AWS Organizations
  • I know how to implement Service Control Policies (SCPs)
  • I understand SCP inheritance and evaluation logic
  • I can deploy AWS Control Tower and configure guardrails
  • I know how to use Account Factory for automated account provisioning
  • I understand delegated administration for security services
  • I can centralize security findings with Security Hub aggregation
  • I know how to secure root account credentials
  • I can design CloudFormation templates with security best practices
  • I understand CloudFormation drift detection
  • I can deploy CloudFormation StackSets across multiple accounts
  • I know how to implement and enforce tagging strategies
  • I can configure AWS Service Catalog portfolios and products
  • I understand Firewall Manager policies (WAF, security groups, Network Firewall)
  • I can share resources securely with AWS RAM
  • I know how to use Macie for data classification and sensitive data discovery
  • I can create AWS Config rules for compliance monitoring
  • I understand Config conformance packs and organization rules
  • I can configure Security Hub compliance standards
  • I know how to use Audit Manager for evidence collection
  • I can identify cost anomalies and unused resources
  • I understand how to use the Well-Architected Tool for security reviews

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (Account Management and Deployment)
  • Domain 6 Bundle 2: Questions 26-50 (Compliance and Security Gaps)
  • Compliance & Governance Bundle: All 50 questions (Governance-specific scenarios)
  • Expected score: 70%+ to proceed

If you scored below 70%:

  • Review SCP evaluation logic and inheritance
  • Practice designing multi-account architectures with Organizations
  • Study Control Tower guardrails (preventive and detective)
  • Focus on Config rules and conformance packs
  • Review Firewall Manager policy types and deployment

Quick Reference Card

Account Management Services:

  • AWS Organizations: Multi-account management with organizational units (OUs)
  • Control Tower: Automated account provisioning with guardrails
  • SCPs: Service Control Policies for organization-wide permission boundaries
  • Delegated Administration: Centralized management of security services

Deployment Services:

  • CloudFormation: Infrastructure as Code (IaC) for consistent deployments
  • Service Catalog: Approved product portfolios for self-service provisioning
  • Firewall Manager: Centralized security policy management
  • AWS RAM: Resource sharing across accounts

Compliance Services:

  • AWS Config: Resource configuration tracking and compliance monitoring
  • Macie: Sensitive data discovery and classification
  • Security Hub: Centralized security findings and compliance checks
  • Audit Manager: Automated evidence collection for compliance frameworks

Governance Services:

  • Trusted Advisor: Best practice checks (security, cost, performance)
  • Cost Explorer: Cost analysis and anomaly detection
  • Well-Architected Tool: Architecture reviews against AWS best practices

Key Concepts:

  • Organizational Unit (OU): Logical grouping of accounts in Organizations
  • SCP: Service Control Policy that limits permissions across accounts
  • Guardrail: Preventive (SCP) or detective (Config rule) control
  • Delegated Administrator: Account designated to manage security services
  • Conformance Pack: Collection of Config rules for compliance frameworks
  • Landing Zone: Multi-account environment with security guardrails (Control Tower)

Multi-Account Strategy:

  • Security Account: Centralized security tooling (Security Hub, GuardDuty)
  • Logging Account: Centralized log storage (CloudTrail, VPC Flow Logs)
  • Shared Services Account: Common services (Active Directory, DNS)
  • Production Accounts: Production workloads (isolated by application/team)
  • Development Accounts: Development and testing (isolated from production)

SCP Best Practices:

  • Deny disabling CloudTrail
  • Deny leaving allowed regions
  • Deny deleting logs
  • Deny disabling security services (GuardDuty, Config)
  • Deny root account usage (except for specific actions)
  • Require encryption for S3 uploads
  • Require MFA for sensitive operations

Decision Points:

  • Multi-account setup → AWS Organizations with Control Tower
  • Account provisioning → Control Tower Account Factory
  • Organization-wide guardrails → SCPs (preventive) + Config rules (detective)
  • Centralized security → Delegated administration in security account
  • Infrastructure deployment → CloudFormation with StackSets
  • Approved services → Service Catalog portfolios
  • Security policy management → Firewall Manager
  • Resource sharing → AWS RAM
  • Data classification → Macie
  • Compliance monitoring → Config rules + conformance packs
  • Evidence collection → Audit Manager
  • Security reviews → Well-Architected Tool

Exam Tips:

  • Know that SCPs don't grant permissions, they only limit what can be granted
  • Understand SCP inheritance: child OUs inherit SCPs from parent OUs
  • Remember that Control Tower uses SCPs and Config rules for guardrails
  • Config rules are detective (detect non-compliance), SCPs are preventive (prevent actions)
  • Delegated administration allows centralized management without sharing root credentials
  • CloudFormation drift detection identifies manual changes to resources
  • Macie uses machine learning to discover sensitive data (PII, credentials)
  • Audit Manager automates evidence collection for compliance frameworks
  • Firewall Manager centrally manages WAF, Shield, security groups, and Network Firewall policies


Chapter Summary

What We Covered

This chapter explored AWS management and security governance across four critical areas:

Centralized Account Deployment and Management

  • Multi-account strategies using AWS Organizations
  • AWS Control Tower deployment and guardrails
  • Service Control Policies (SCPs) for account-level controls
  • Centralized security management and finding aggregation
  • Root account security best practices

Secure and Consistent Deployment Strategy

  • Infrastructure as Code (IaC) with CloudFormation
  • Tagging strategies for resource organization and access control
  • AWS Service Catalog for approved service portfolios
  • AWS Firewall Manager for centralized security policy management
  • Resource sharing with AWS Resource Access Manager (RAM)

Compliance Evaluation of AWS Resources

  • Data classification using Macie
  • AWS Config rules for compliance monitoring
  • Evidence collection with Security Hub and Audit Manager
  • Automated compliance reporting and remediation

Identifying Security Gaps

  • Cost and usage anomaly identification
  • Identifying unused resources with Trusted Advisor and Cost Explorer
  • AWS Well-Architected Tool for security reviews
  • Attack surface reduction strategies

Critical Takeaways

  1. Organizations is foundational: Use AWS Organizations to manage multiple accounts with centralized billing and governance
  2. Control Tower automates setup: Use Control Tower to set up landing zones with pre-configured guardrails and account factory
  3. SCPs set guardrails: Service Control Policies define maximum permissions for accounts (cannot grant permissions, only restrict)
  4. Config monitors compliance: Use AWS Config rules to continuously monitor resource compliance with organizational standards
  5. Macie discovers sensitive data: Enable Macie to automatically discover and classify sensitive data in S3 buckets
  6. Audit Manager collects evidence: Use Audit Manager to automate evidence collection for compliance audits
  7. CloudFormation for consistency: Use CloudFormation templates to deploy resources consistently across accounts
  8. Service Catalog controls deployments: Use Service Catalog to provide approved, pre-configured products to users
  9. Firewall Manager centralizes policies: Use Firewall Manager to centrally manage WAF rules, Shield protections, and security group policies
  10. Tagging enables governance: Implement consistent tagging strategies for cost allocation, access control, and automation
  11. Well-Architected reviews: Use the Well-Architected Tool to identify security gaps and improvement opportunities
  12. Trusted Advisor for optimization: Use Trusted Advisor to identify security risks and cost optimization opportunities

Self-Assessment Checklist

Test yourself before moving on:

Account Management:

  • I can design multi-account strategies using AWS Organizations
  • I understand how to deploy and configure AWS Control Tower
  • I know how to write and apply Service Control Policies (SCPs)
  • I can configure delegated administration for security services
  • I understand root account security best practices

Deployment Strategy:

  • I can write secure CloudFormation templates with drift detection
  • I understand how to implement and enforce tagging strategies
  • I know how to use Service Catalog to deploy approved services
  • I can configure Firewall Manager policies across accounts
  • I understand how to share resources securely with AWS RAM

Compliance Evaluation:

  • I can configure Macie to discover and classify sensitive data
  • I understand how to create and deploy AWS Config rules
  • I know how to use Audit Manager for compliance assessments
  • I can automate compliance reporting and evidence collection
  • I understand conformance packs for multi-account compliance

Security Gap Identification:

  • I can identify cost and usage anomalies that indicate security issues
  • I understand how to use Trusted Advisor for security recommendations
  • I know how to conduct Well-Architected reviews for security
  • I can identify and remove unused resources to reduce attack surface
  • I understand how to optimize security posture continuously

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (Account Management and Deployment)
  • Domain 6 Bundle 2: Questions 26-50 (Compliance and Security Gaps)
  • Compliance & Governance Bundle: Questions 1-50 (Governance-specific scenarios)

Expected score: 75%+ to proceed confidently

If you scored below 75%:

  • Review SCP evaluation logic and how SCPs interact with IAM policies
  • Practice writing CloudFormation templates with security best practices
  • Focus on understanding Config rule types (managed vs custom)
  • Review Firewall Manager policy types and deployment strategies

Quick Reference Card

Key Services:

  • Organizations: Multi-account management with consolidated billing
  • Control Tower: Automated landing zone setup with guardrails
  • Config: Resource configuration tracking and compliance monitoring
  • Macie: Sensitive data discovery and classification in S3
  • Audit Manager: Automated evidence collection for compliance audits
  • CloudFormation: Infrastructure as Code for consistent deployments
  • Service Catalog: Approved product portfolios for self-service
  • Firewall Manager: Centralized security policy management
  • Trusted Advisor: Best practice recommendations for security and cost
  • Well-Architected Tool: Framework for reviewing architectures

Key Concepts:

  • Landing Zone: Multi-account environment with security guardrails (Control Tower)
  • Guardrails: Preventive (SCPs) and detective (Config rules) controls
  • SCP: Service Control Policy (maximum permissions for accounts)
  • Delegated Administration: Allowing member accounts to manage security services
  • Conformance Pack: Collection of Config rules for compliance frameworks
  • Drift Detection: Identifying manual changes to CloudFormation stacks
  • Tag Policy: Enforcing consistent tagging across organization
  • Account Factory: Automated account provisioning with Control Tower

Service Control Policy (SCP) Rules:

  • SCPs affect all users and roles in an account, including root
  • SCPs do NOT affect service-linked roles
  • SCPs do NOT grant permissions, only restrict them
  • SCPs are inherited down the OU hierarchy
  • Explicit deny in SCP always wins

Decision Points:

  • Multi-account management → Organizations (foundational)
  • Automated account setup → Control Tower (landing zone + guardrails)
  • Account-level restrictions → Service Control Policies (SCPs)
  • Resource compliance monitoring → AWS Config rules
  • Sensitive data discovery → Macie (S3 buckets)
  • Compliance evidence → Audit Manager (automated collection)
  • Consistent deployments → CloudFormation (IaC)
  • Approved services → Service Catalog (portfolios)
  • Centralized security policies → Firewall Manager (WAF, Shield, security groups)
  • Resource sharing → AWS RAM (cross-account)
  • Security recommendations → Trusted Advisor (automated checks)
  • Architecture review → Well-Architected Tool (security pillar)
  • Cost anomalies → Cost Explorer with anomaly detection
  • Unused resources → Trusted Advisor + Cost Explorer

Config Rule Types:

  • Managed Rules: Pre-built rules by AWS (e.g., encrypted-volumes, required-tags)
  • Custom Rules: Lambda functions for custom compliance checks
  • Conformance Packs: Collections of rules for compliance frameworks (PCI-DSS, HIPAA)

Firewall Manager Policy Types:

  • WAF policies: Centrally manage WAF rules across accounts
  • Shield Advanced policies: Manage Shield Advanced protections
  • Security group policies: Audit and enforce security group rules
  • Network Firewall policies: Manage Network Firewall rules
  • Route 53 Resolver DNS Firewall policies: Manage DNS filtering

  • Custom Rules: Lambda functions for custom compliance checks
  • Conformance Packs: Collections of Config rules for specific compliance frameworks (PCI-DSS, HIPAA, etc.)

Macie Data Identifiers:

  • Managed Data Identifiers: Pre-built patterns for PII, financial data, credentials
  • Custom Data Identifiers: Regular expressions for organization-specific sensitive data

Chapter Summary

What We Covered

This chapter covered Management and Security Governance, accounting for 14% of the SCS-C02 exam. We explored four major task areas:

Task 6.1: Centrally Deploy and Manage AWS Accounts

  • Deploying and configuring AWS Organizations for multi-account management
  • Determining when and how to deploy AWS Control Tower (landing zone, guardrails, account factory)
  • Implementing Service Control Policies (SCPs) to enforce account-level restrictions
  • Centralizing security services and aggregating findings (Security Hub, Config aggregators)
  • Securing AWS account root user credentials

Task 6.2: Secure and Consistent Deployment Strategy

  • Using CloudFormation for consistent and secure infrastructure deployment
  • Implementing and enforcing multi-account tagging strategies
  • Configuring and deploying AWS Service Catalog portfolios for approved services
  • Deploying Firewall Manager to enforce security policies across accounts
  • Securely sharing resources across AWS accounts using AWS RAM

Task 6.3: Evaluate Compliance of AWS Resources

  • Identifying sensitive data using Macie (managed and custom data identifiers)
  • Creating AWS Config rules for detection of noncompliant resources
  • Collecting and organizing evidence using Security Hub and Audit Manager

Task 6.4: Identify Security Gaps

  • Identifying anomalies based on resource utilization and cost trends
  • Identifying unused resources using Trusted Advisor and Cost Explorer
  • Using the AWS Well-Architected Tool to identify security gaps

Critical Takeaways

  1. Organizations is Foundational: AWS Organizations is the foundation for multi-account management. Enable it first, then add Control Tower, SCPs, and centralized logging.

  2. Control Tower Automates Best Practices: Control Tower sets up a landing zone with pre-configured guardrails, account factory, and centralized logging. Use it for new multi-account environments.

  3. SCPs are Account-Level Guardrails: Service Control Policies (SCPs) restrict what actions are allowed in member accounts, regardless of IAM policies. Use them to prevent risky actions (e.g., disabling CloudTrail).

  4. Config Rules for Continuous Compliance: AWS Config continuously monitors resource configurations and evaluates them against rules. Use conformance packs for compliance frameworks (PCI-DSS, HIPAA).

  5. Macie Discovers Sensitive Data: Macie automatically discovers and classifies sensitive data in S3 buckets (PII, financial data, credentials). Use it to identify data that needs protection.

  6. CloudFormation for Consistency: Use CloudFormation (or Terraform) for infrastructure as code. This ensures consistent, repeatable deployments and enables drift detection.

  7. Service Catalog for Approved Services: Use Service Catalog to provide a curated list of approved services and configurations. This prevents shadow IT and ensures compliance.

  8. Firewall Manager for Centralized Policies: Use Firewall Manager to centrally manage WAF rules, Shield protections, and security group policies across all accounts.

Self-Assessment Checklist

Test yourself before moving on. You should be able to:

Multi-Account Management:

  • Set up AWS Organizations with organizational units (OUs)
  • Deploy AWS Control Tower and understand its components (landing zone, guardrails, account factory)
  • Create Service Control Policies (SCPs) to restrict account-level actions
  • Configure delegated administration for Security Hub and Config
  • Secure the root account with MFA and restrict its use

Deployment Strategy:

  • Create CloudFormation templates with security best practices
  • Implement CloudFormation drift detection to identify configuration changes
  • Design a multi-account tagging strategy for cost allocation and access control
  • Configure Service Catalog portfolios with approved products
  • Deploy Firewall Manager policies for WAF and security groups
  • Share resources across accounts using AWS RAM

Compliance Evaluation:

  • Enable Macie and configure sensitive data discovery jobs
  • Create custom data identifiers for organization-specific sensitive data
  • Configure AWS Config rules for compliance monitoring
  • Deploy conformance packs for compliance frameworks (PCI-DSS, HIPAA)
  • Set up Audit Manager assessments for evidence collection

Security Gap Identification:

  • Use Cost Explorer to identify cost anomalies indicating security issues
  • Run Trusted Advisor security checks to identify unused resources
  • Conduct a Well-Architected Review focusing on the security pillar
  • Identify and remediate security gaps based on recommendations

Decision-Making:

  • Choose between Organizations and Control Tower for multi-account management
  • Determine when to use SCPs vs. IAM policies
  • Select between Config rules and Security Hub standards for compliance
  • Decide when to use Macie vs. manual data classification

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-35 (focus on multi-account management and deployment)
  • Domain 6 Bundle 2: Questions 36-70 (focus on compliance and security gap identification)
  • Compliance & Governance Bundle: Questions covering Config, Audit Manager, Control Tower, Service Catalog
  • Full Practice Test 1: Domain 6 questions (7 questions, 14% of exam)

Expected Score: 70%+ to proceed confidently

If you scored below 70%:

  • Review sections:
    • Service Control Policies (if you struggled with account-level restriction questions)
    • AWS Config Rules (if you struggled with compliance monitoring questions)
    • Control Tower Components (if you struggled with landing zone questions)
    • Macie Data Discovery (if you struggled with sensitive data identification questions)
  • Focus on:
    • Understanding the differences between SCPs, IAM policies, and permissions boundaries
    • Memorizing common Config rules for compliance (encrypted-volumes, required-tags, etc.)
    • Practicing CloudFormation template creation with security best practices
    • Understanding when to use Control Tower vs. Organizations alone

Quick Reference Card

Key Services:

  • Organizations: Multi-account management with organizational units (OUs) and SCPs
  • Control Tower: Automated landing zone setup with guardrails and account factory
  • Config: Resource configuration tracking and compliance monitoring
  • Macie: Sensitive data discovery and classification in S3
  • Audit Manager: Automated evidence collection for compliance audits
  • Service Catalog: Curated catalog of approved AWS services and configurations
  • Firewall Manager: Centralized management of WAF, Shield, and security group policies
  • CloudFormation: Infrastructure as code for consistent deployments
  • Trusted Advisor: Automated checks for security, cost, performance, and fault tolerance
  • Well-Architected Tool: Framework for reviewing architectures against best practices

Key Concepts:

  • Landing Zone: Pre-configured multi-account environment with security guardrails
  • Guardrails: Preventive (SCPs) and detective (Config rules) controls
  • Account Factory: Automated account provisioning with baseline configurations
  • Conformance Pack: Collection of Config rules for specific compliance frameworks
  • Delegated Administration: Allowing member accounts to manage security services
  • Drift Detection: Identifying configuration changes from CloudFormation templates
  • Tagging Strategy: Consistent tagging for cost allocation, access control, and automation

Decision Points:

  • Multi-account management → Organizations (foundational)
  • Automated account setup → Control Tower (landing zone + guardrails)
  • Account-level restrictions → Service Control Policies (SCPs)
  • Resource compliance monitoring → AWS Config rules
  • Sensitive data discovery → Macie (S3 buckets)
  • Compliance evidence → Audit Manager (automated collection)
  • Consistent deployments → CloudFormation (IaC)
  • Approved services → Service Catalog (portfolios)
  • Centralized security policies → Firewall Manager (WAF, Shield, security groups)
  • Resource sharing → AWS RAM (cross-account)
  • Security recommendations → Trusted Advisor (automated checks)
  • Architecture review → Well-Architected Tool (security pillar)
  • Cost anomalies → Cost Explorer with anomaly detection
  • Unused resources → Trusted Advisor + Cost Explorer

Config Rule Types:

  • Managed Rules: Pre-built rules by AWS (e.g., encrypted-volumes, required-tags)
  • Custom Rules: Lambda functions for custom compliance checks
  • Conformance Packs: Collections of Config rules for specific compliance frameworks (PCI-DSS, HIPAA, etc.)

Macie Data Identifiers:

  • Managed Data Identifiers: Pre-built patterns for PII, financial data, credentials
  • Custom Data Identifiers: Regular expressions for organization-specific sensitive data

Next Steps

Before moving to Domain 7 (Integration):

  1. Review the Quick Reference Card and ensure you can recall all key services
  2. Practice creating Service Control Policies (SCPs) with deny statements
  3. Experiment with AWS Config rules and conformance packs
  4. Set up Macie and run a sensitive data discovery job

Moving Forward:

  • Domain 7 (Integration) will show how all six domains work together in real-world scenarios
  • Understanding Organizations and Control Tower is essential for enterprise security
  • Config rules and Macie will be combined with other security services for comprehensive compliance

Chapter Summary

What We Covered

This chapter covered Domain 6: Management and Security Governance (14% of the exam), focusing on four critical task areas:

Task 6.1: Centrally deploy and manage AWS accounts

  • Multi-account strategies using AWS Organizations
  • AWS Control Tower deployment and guardrails
  • Service Control Policies (SCPs) for account-level restrictions
  • Centralized security management using delegated administration
  • Root account security best practices

Task 6.2: Secure and consistent deployment strategy

  • Infrastructure as Code (IaC) using CloudFormation
  • Tagging strategies for resource organization and access control
  • AWS Service Catalog for approved service deployment
  • Firewall Manager for centralized security policy management
  • Resource sharing using AWS RAM

Task 6.3: Evaluate compliance of AWS resources

  • Data classification using Macie
  • AWS Config rules for compliance monitoring
  • Evidence collection using Security Hub and Audit Manager

Task 6.4: Identify security gaps

  • Cost and usage anomaly identification
  • Identifying unused resources using Trusted Advisor and Cost Explorer
  • AWS Well-Architected Tool for security reviews
  • Attack surface reduction strategies

Critical Takeaways

  1. Organizations is the foundation: Create a multi-account structure with OUs for different environments (dev, test, prod) and workloads.

  2. Control Tower automates account setup: Provides pre-configured guardrails and account factory for consistent account provisioning.

  3. SCPs are account-level guardrails: Applied at the organization or OU level. Cannot grant permissions, only restrict them. Use to prevent risky actions.

  4. Delegated administration reduces root account usage: Delegate security service management to a dedicated security account.

  5. CloudFormation for consistent deployments: Use StackSets to deploy resources across multiple accounts and regions.

  6. Tagging is essential: Use tags for cost allocation, access control (ABAC), and resource organization. Enforce tagging with tag policies.

  7. Service Catalog for approved services: Create portfolios of approved CloudFormation templates. Users can self-service without admin access.

  8. Firewall Manager for centralized policies: Deploy WAF rules, security group policies, and Network Firewall rules across accounts.

  9. Config for compliance monitoring: Use managed rules or custom rules to detect non-compliant resources. Use conformance packs for frameworks (PCI-DSS, HIPAA).

  10. Macie for sensitive data discovery: Automatically discover PII, financial data, and credentials in S3 buckets. Use custom data identifiers for organization-specific data.

Self-Assessment Checklist

Test yourself before moving to Domain 7 (Integration). You should be able to:

Multi-Account Management:

  • Design a multi-account structure using Organizations
  • Configure Control Tower with guardrails
  • Write SCPs to restrict account-level actions
  • Configure delegated administration for security services
  • Explain root account security best practices
  • Design cross-account roles for centralized management

Deployment Strategy:

  • Write CloudFormation templates with security best practices
  • Configure CloudFormation drift detection
  • Design a tagging strategy for access control and cost allocation
  • Create Service Catalog portfolios with constraints
  • Configure Firewall Manager policies for WAF and security groups
  • Share resources across accounts using AWS RAM

Compliance Monitoring:

  • Configure Macie for sensitive data discovery
  • Create custom data identifiers for organization-specific data
  • Write AWS Config rules for compliance monitoring
  • Deploy conformance packs for compliance frameworks
  • Configure Security Hub compliance standards
  • Use Audit Manager to collect evidence for audits

Security Gap Identification:

  • Use Cost Explorer to identify cost anomalies
  • Use Trusted Advisor to identify unused resources
  • Use Well-Architected Tool to review security posture
  • Design an attack surface reduction strategy
  • Identify and remove unnecessary network access

Practice Questions

Recommended Practice Test Bundles:

  • Domain 6 Bundle 1: Questions 431-480 (covers all Task 6.1, 6.2, 6.3, 6.4 topics)
  • Domain 6 Bundle 2: Questions 481-500 (additional practice on weak areas)
  • Compliance & Governance Bundle: Questions covering Config, Audit Manager, Control Tower, Service Catalog

Expected Score: 75%+ to proceed confidently

If you scored below 75%:

  • Review sections:
    • Service Control Policies (if you struggled with SCP questions)
    • CloudFormation StackSets (if you struggled with multi-account deployment questions)
    • AWS Config Rules (if you struggled with compliance monitoring questions)
    • Macie Data Identifiers (if you struggled with sensitive data discovery questions)
  • Focus on:
    • Understanding the difference between SCPs and IAM policies
    • Memorizing when to use Control Tower vs. Organizations alone
    • Practicing Config rule creation for compliance monitoring
    • Understanding Macie managed data identifiers vs. custom data identifiers

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • Organizations: Multi-account management with SCPs
  • Control Tower: Automated account setup with guardrails
  • CloudFormation: Infrastructure as Code (IaC)
  • Service Catalog: Approved service portfolios
  • Firewall Manager: Centralized security policy management
  • AWS RAM: Resource sharing across accounts
  • Config: Resource configuration tracking and compliance monitoring
  • Macie: Sensitive data discovery in S3
  • Audit Manager: Evidence collection for audits
  • Trusted Advisor: Security and cost recommendations
  • Well-Architected Tool: Architecture review framework

Key Concepts:

  • Service Control Policy (SCP): Account-level guardrails (deny only)
  • Guardrails: Control Tower policies (preventive or detective)
  • Delegated Administration: Delegate service management to non-root accounts
  • StackSets: Deploy CloudFormation stacks across accounts and regions
  • Conformance Pack: Collection of Config rules for compliance frameworks
  • Managed Data Identifier: Pre-built Macie patterns for PII, financial data, credentials
  • Custom Data Identifier: Regular expressions for organization-specific sensitive data
  • Tag Policy: Enforce tagging standards across accounts

Decision Points:

  • Multi-account structure → Organizations (with OUs for environments)
  • Automated account setup → Control Tower (with guardrails)
  • Account-level restrictions → SCPs (deny policies)
  • Consistent deployments → CloudFormation StackSets
  • Approved services → Service Catalog (portfolios)
  • Centralized security policies → Firewall Manager
  • Resource sharing → AWS RAM (cross-account)
  • Compliance monitoring → Config (rules and conformance packs)
  • Sensitive data discovery → Macie (managed and custom identifiers)
  • Evidence collection → Audit Manager (automated)
  • Security recommendations → Trusted Advisor (automated checks)
  • Architecture review → Well-Architected Tool (security pillar)
  • Cost anomalies → Cost Explorer with anomaly detection
  • Unused resources → Trusted Advisor + Cost Explorer

Config Rule Types:

  • Managed Rules: Pre-built rules by AWS (e.g., encrypted-volumes, required-tags)
  • Custom Rules: Lambda functions for custom compliance checks
  • Conformance Packs: Collections of Config rules for specific compliance frameworks (PCI-DSS, HIPAA, etc.)

Macie Data Identifiers:

  • Managed Data Identifiers: Pre-built patterns for PII, financial data, credentials
  • Custom Data Identifiers: Regular expressions for organization-specific sensitive data

Common Patterns:

  • Organizations + Control Tower + SCPs → Multi-account governance
  • CloudFormation StackSets + Service Catalog → Consistent deployments
  • Config + Conformance Packs → Compliance monitoring
  • Macie + EventBridge + Lambda → Automated sensitive data remediation
  • Firewall Manager + WAF → Centralized web application protection
  • Trusted Advisor + Cost Explorer → Cost optimization and security recommendations

Chapter Summary

What We Covered

This chapter covered Domain 6: Management and Security Governance (14% of the exam), focusing on four critical task areas:

Task 6.1: Centrally deploy and manage AWS accounts

  • Multi-account strategies with AWS Organizations
  • AWS Control Tower deployment and guardrails
  • Service Control Policies (SCPs) to enforce organizational policies
  • Centralized security management with delegated administration
  • Root account security best practices

Task 6.2: Secure and consistent deployment strategy

  • Infrastructure as Code (IaC) with CloudFormation (template hardening, drift detection)
  • Tagging strategies for resource organization and access control
  • AWS Service Catalog for deploying approved services
  • Firewall Manager for centralized security policy enforcement
  • Resource sharing with AWS Resource Access Manager (RAM)

Task 6.3: Evaluate compliance of AWS resources

  • Data classification using Macie for sensitive data discovery
  • AWS Config rules for detecting noncompliant resources
  • Evidence collection using Security Hub and Audit Manager

Task 6.4: Identify security gaps

  • Cost and usage anomaly identification
  • Identifying unused resources with Trusted Advisor and Cost Explorer
  • AWS Well-Architected Tool for security reviews
  • Attack surface reduction strategies

Critical Takeaways

  1. Organizations is the foundation of multi-account strategy: Use it to centrally manage accounts, apply SCPs, and enable cross-account services.

  2. Control Tower automates account setup: It creates a landing zone with guardrails (preventive and detective controls) and account factory for provisioning new accounts.

  3. SCPs set maximum permissions: They don't grant permissions, they limit what IAM policies can grant. Apply at OU or account level. Even root user is restricted by SCPs.

  4. CloudFormation enables IaC: Use it to deploy infrastructure consistently. Enable drift detection to identify manual changes. Use StackSets for multi-account/region deployments.

  5. Tagging is essential for governance: Use tags for cost allocation, access control (ABAC), automation, and resource organization. Enforce tagging with SCPs or Config rules.

  6. Service Catalog provides self-service: Create portfolios of approved CloudFormation templates. Users can deploy pre-approved resources without needing full IAM permissions.

  7. Firewall Manager centralizes security policies: Deploy WAF rules, Shield protections, security group policies, and Network Firewall rules across all accounts from a central location.

  8. Config tracks resource configuration: Use Config rules to detect noncompliant resources. Use conformance packs for pre-built compliance frameworks (PCI-DSS, HIPAA).

  9. Macie discovers sensitive data: It uses ML to identify PII, financial data, and credentials in S3 buckets. Automatically classifies data and generates findings.

  10. Audit Manager collects evidence: It continuously collects evidence for compliance audits. Maps evidence to compliance frameworks (SOC 2, PCI-DSS, GDPR).

Self-Assessment Checklist

Test yourself before moving to the next chapter. You should be able to:

Multi-Account Management:

  • Design an AWS Organizations structure with OUs for different environments
  • Deploy AWS Control Tower and configure guardrails
  • Create an SCP to prevent account-level actions (e.g., leaving the organization)
  • Set up delegated administration for Security Hub and GuardDuty
  • Secure the root account with MFA and restrict its use

Deployment Strategy:

  • Create a CloudFormation template with security best practices
  • Enable CloudFormation drift detection to identify manual changes
  • Design a tagging strategy for cost allocation and access control
  • Create a Service Catalog portfolio with approved products
  • Deploy Firewall Manager policies across multiple accounts

Compliance Evaluation:

  • Enable Macie to discover sensitive data in S3 buckets
  • Create custom Config rules to detect noncompliant resources
  • Deploy a Config conformance pack for PCI-DSS compliance
  • Set up Audit Manager to collect evidence for SOC 2 audit
  • Use Security Hub compliance standards to track security posture

Security Gap Identification:

  • Use Cost Explorer to identify cost anomalies
  • Run Trusted Advisor security checks to find unused resources
  • Perform a Well-Architected Review focusing on the Security Pillar
  • Identify and remove unused security groups and IAM roles
  • Design an attack surface reduction strategy

Practice Questions

Try these from your practice test bundles:

  • Domain 6 Bundle 1: Questions 1-25 (focus on multi-account management and deployment)
  • Domain 6 Bundle 2: Questions 26-50 (focus on compliance and security gaps)
  • Compliance Governance Bundle: Questions covering Config, Audit Manager, Control Tower, Service Catalog
  • Full Practice Test 1: Domain 6 questions (7 questions, 14% of exam)

Expected score: 70%+ to proceed confidently

If you scored below 70%:

  • Review the differences between Organizations, Control Tower, and SCPs
  • Practice creating CloudFormation templates with security best practices
  • Focus on understanding Config rules and conformance packs
  • Revisit Macie data classification and Audit Manager evidence collection

Quick Reference Card

Copy this to your notes for quick review:

Key Services:

  • Organizations: Multi-account management with SCPs
  • Control Tower: Automated landing zone with guardrails
  • CloudFormation: Infrastructure as Code (IaC)
  • Service Catalog: Self-service deployment of approved resources
  • Firewall Manager: Centralized security policy management
  • Config: Resource configuration tracking and compliance
  • Macie: Sensitive data discovery and classification
  • Audit Manager: Evidence collection for compliance audits
  • Trusted Advisor: Best practice recommendations
  • Well-Architected Tool: Architecture reviews

Key Concepts:

  • Multi-Account Strategy: Separate accounts for different environments (dev, test, prod)
  • Landing Zone: Pre-configured multi-account environment with guardrails
  • Guardrails: Preventive (SCPs) and detective (Config rules) controls
  • SCP: Service Control Policy that limits account permissions
  • Drift Detection: Identifying manual changes to CloudFormation stacks
  • Tagging Strategy: Consistent tags for cost allocation and access control
  • Conformance Pack: Pre-built set of Config rules for compliance frameworks
  • Delegated Administration: Allowing a member account to manage a service for the organization
  • Attack Surface: All points where an attacker could enter or extract data

Decision Points:

  • Need multi-account management → Organizations with OUs and SCPs
  • Need automated account setup → Control Tower with account factory
  • Need to enforce policies → SCPs (preventive) or Config rules (detective)
  • Need consistent deployments → CloudFormation with StackSets
  • Need self-service deployments → Service Catalog portfolios
  • Need centralized security policies → Firewall Manager
  • Need to track configuration changes → Config with Config rules
  • Need to find sensitive data → Macie for S3 buckets
  • Need compliance evidence → Audit Manager with frameworks
  • Need to find unused resources → Trusted Advisor or Cost Explorer
  • Need architecture review → Well-Architected Tool

Common Troubleshooting:

  • SCP not working → Check SCP is attached to correct OU/account, check policy syntax
  • Control Tower deployment failing → Check prerequisites (no existing Config, CloudTrail)
  • CloudFormation drift detected → Identify manual changes, update template, re-deploy
  • Config rule not detecting → Check rule configuration, IAM permissions, Config recorder
  • Macie not finding data → Check S3 bucket permissions, Macie job configuration
  • Firewall Manager policy not applying → Check delegated admin, account membership

You're now ready for Chapter 7: Integration!

The next chapter will show you how all six domains work together in real-world scenarios.


Integration & Advanced Topics: Putting It All Together

Cross-Domain Scenarios

The AWS Certified Security - Specialty exam tests your ability to integrate concepts across multiple domains. Real-world security architectures combine threat detection, logging, infrastructure security, IAM, data protection, and governance. This chapter covers common cross-domain scenarios you'll encounter on the exam.

Scenario Type 1: Incident Response with Multi-Domain Integration

What it tests: Understanding of how threat detection, logging, IAM, and automation work together during security incidents.

How to approach:

  1. Detection: Identify which service detects the threat (GuardDuty, Security Hub, Macie, Inspector)
  2. Investigation: Determine logging sources needed (CloudTrail, VPC Flow Logs, CloudWatch Logs)
  3. Response: Choose appropriate response actions (isolate resources, rotate credentials, block IPs)
  4. Automation: Implement automated response (EventBridge, Lambda, Step Functions)

📊 Incident Response Integration Diagram:

graph TB
    subgraph "Detection Layer"
        GD[GuardDuty<br/>Threat Detection]
        SH[Security Hub<br/>Finding Aggregation]
        MACIE[Macie<br/>Data Discovery]
    end
    
    subgraph "Investigation Layer"
        CT[CloudTrail<br/>API Logs]
        VPC[VPC Flow Logs<br/>Network Traffic]
        DET[Detective<br/>Behavior Analysis]
    end
    
    subgraph "Response Layer"
        EB[EventBridge<br/>Event Routing]
        LAMBDA[Lambda<br/>Automated Response]
        SSM[Systems Manager<br/>Remediation]
    end
    
    subgraph "Affected Resources"
        EC2[Compromised EC2]
        IAM_ROLE[Compromised IAM Role]
        S3[Exposed S3 Bucket]
    end
    
    GD --> SH
    MACIE --> SH
    
    SH --> EB
    EB --> LAMBDA
    
    LAMBDA --> CT
    LAMBDA --> VPC
    LAMBDA --> DET
    
    LAMBDA --> SSM
    SSM --> EC2
    SSM --> IAM_ROLE
    SSM --> S3

    style GD fill:#ffebee
    style SH fill:#fff3e0
    style EB fill:#e1f5fe
    style LAMBDA fill:#c8e6c9
    style EC2 fill:#f3e5f5

See: diagrams/08_integration_incident_response.mmd

Diagram Explanation:
The incident response integration diagram shows how multiple AWS services work together during a security incident. The Detection Layer (red/orange) includes GuardDuty for threat detection, Security Hub for finding aggregation, and Macie for sensitive data discovery. When a threat is detected, findings flow to Security Hub. The Investigation Layer includes CloudTrail for API logs, VPC Flow Logs for network traffic, and Detective for behavior analysis. The Response Layer (blue/green) uses EventBridge to route security events to Lambda functions, which implement automated response actions through Systems Manager. Affected Resources (purple) like compromised EC2 instances, IAM roles, or exposed S3 buckets are automatically remediated. This integration provides end-to-end incident response: detect → investigate → respond → remediate.

Example Question Pattern:
"A company's GuardDuty has detected an EC2 instance communicating with a known malicious IP address. The security team needs to automatically isolate the instance, capture forensic data, and notify the security team. What is the MOST operationally efficient solution?"

Solution Approach:

  1. Detection: GuardDuty finding "UnauthorizedAccess:EC2/MaliciousIPCaller.Custom"
  2. Automation: EventBridge rule matches GuardDuty finding type
  3. Isolation: Lambda function modifies security group to deny all traffic
  4. Forensics: Lambda creates EBS snapshot and memory dump
  5. Notification: Lambda publishes to SNS topic for security team
  6. Investigation: Security team uses Detective to analyze behavior graph

Detailed Example: Automated Response to Compromised Credentials
GuardDuty detects "UnauthorizedAccess:IAMUser/InstanceCredentialExfiltration" - an IAM role's temporary credentials are being used from an external IP address. An EventBridge rule triggers a Lambda function. The Lambda function: (1) Retrieves the IAM role name from the GuardDuty finding, (2) Attaches an inline policy to the role denying all actions, (3) Calls STS to revoke all existing sessions for the role, (4) Creates a CloudTrail Insights query to find all API calls made with the compromised credentials, (5) Sends detailed notification to SNS topic with finding details and actions taken, (6) Creates a Security Hub custom action for manual review. The security team receives the notification, reviews the CloudTrail logs to assess impact, and determines if the role was legitimately used from a new location or if it was compromised. This automated response contains the threat within seconds while preserving evidence for investigation.

Scenario Type 2: Data Protection with Encryption and Access Control

What it tests: Understanding of how KMS, IAM, S3, and logging work together to protect sensitive data.

How to approach:

  1. Encryption: Choose appropriate encryption method (SSE-S3, SSE-KMS, SSE-C, client-side)
  2. Access Control: Implement IAM policies, bucket policies, and KMS key policies
  3. Audit: Enable CloudTrail logging for data access and encryption operations
  4. Compliance: Use S3 Object Lock, versioning, and MFA Delete for immutability

📊 Data Protection Integration Diagram:

graph TB
    subgraph "Data Layer"
        S3[S3 Bucket<br/>Encrypted Objects]
        RDS[RDS Database<br/>Encrypted Storage]
    end
    
    subgraph "Encryption Layer"
        KMS[KMS Customer<br/>Managed Key]
        POLICY[KMS Key Policy<br/>Access Control]
    end
    
    subgraph "Access Control Layer"
        IAM_POL[IAM Policies<br/>User Permissions]
        BUCKET_POL[S3 Bucket Policy<br/>Resource Permissions]
        VPC_EP[VPC Endpoint Policy<br/>Network Control]
    end
    
    subgraph "Audit Layer"
        CT[CloudTrail<br/>API Logs]
        S3_LOG[S3 Access Logs<br/>Object Access]
        CW[CloudWatch Logs<br/>Metrics & Alarms]
    end
    
    S3 --> KMS
    RDS --> KMS
    KMS --> POLICY
    
    IAM_POL --> S3
    BUCKET_POL --> S3
    VPC_EP --> S3
    
    S3 --> CT
    S3 --> S3_LOG
    KMS --> CT
    CT --> CW

    style S3 fill:#c8e6c9
    style RDS fill:#c8e6c9
    style KMS fill:#fff3e0
    style IAM_POL fill:#e1f5fe
    style CT fill:#f3e5f5

See: diagrams/08_integration_data_protection.mmd

Diagram Explanation:
The data protection integration diagram shows how encryption, access control, and auditing work together. The Data Layer (green) includes S3 buckets and RDS databases with encrypted storage. The Encryption Layer (orange) uses KMS customer-managed keys with key policies controlling who can use the keys. The Access Control Layer (blue) implements defense-in-depth with IAM policies (user permissions), S3 bucket policies (resource permissions), and VPC endpoint policies (network control). The Audit Layer (purple) logs all access with CloudTrail (API calls), S3 access logs (object access), and CloudWatch (metrics and alarms). This multi-layered approach ensures data is encrypted, access is controlled, and all operations are audited.

Example Question Pattern:
"A company stores sensitive financial data in S3 and needs to ensure only authorized users can decrypt the data. The company must maintain audit logs of all encryption and decryption operations. What is the MOST secure solution?"

Solution Approach:

  1. Encryption: Use SSE-KMS with customer-managed key (not SSE-S3)
  2. Key Policy: Configure KMS key policy to allow only specific IAM roles
  3. Bucket Policy: Deny s3:PutObject unless encryption header present
  4. Audit: CloudTrail logs all KMS Decrypt operations with user identity
  5. Monitoring: CloudWatch alarm on unusual KMS API call patterns

Detailed Example: Multi-Layer Data Protection for Compliance
A healthcare company stores patient records in S3 and must comply with HIPAA. They implement: (1) SSE-KMS encryption with a customer-managed key named "PatientRecordsKey", (2) KMS key policy allowing only the Healthcare application's IAM role to decrypt, (3) S3 bucket policy denying all access except through VPC endpoint, (4) VPC endpoint policy allowing only specific S3 buckets, (5) S3 Object Lock in Compliance mode with 7-year retention, (6) MFA Delete enabled requiring MFA to delete versions, (7) CloudTrail logging all S3 and KMS API calls to a separate audit account, (8) CloudWatch metric filter alerting on any KMS Decrypt calls from unexpected IP addresses. This architecture provides encryption at rest, fine-grained access control, immutable storage, and comprehensive audit trails - meeting HIPAA requirements for data protection.

Scenario Type 3: Network Security with Defense-in-Depth

What it tests: Understanding of how VPC, security groups, NACLs, WAF, and monitoring work together for network security.

How to approach:

  1. Perimeter: Implement edge protection (WAF, Shield, CloudFront)
  2. Network Segmentation: Use VPCs, subnets, security groups, NACLs
  3. Traffic Inspection: Deploy Network Firewall, Traffic Mirroring
  4. Monitoring: Enable VPC Flow Logs, WAF logs, CloudWatch metrics
  5. Private Connectivity: Use VPC endpoints, PrivateLink, Transit Gateway

📊 Network Security Integration Diagram:

graph TB
    subgraph "Edge Layer"
        CF[CloudFront<br/>CDN]
        WAF[AWS WAF<br/>Application Firewall]
        SHIELD[AWS Shield<br/>DDoS Protection]
    end
    
    subgraph "VPC Layer"
        ALB[Application<br/>Load Balancer]
        SG[Security Groups<br/>Stateful Firewall]
        NACL[Network ACLs<br/>Stateless Firewall]
    end
    
    subgraph "Application Layer"
        EC2[EC2 Instances<br/>Private Subnet]
        RDS[RDS Database<br/>Private Subnet]
    end
    
    subgraph "Monitoring Layer"
        FLOW[VPC Flow Logs]
        WAF_LOG[WAF Logs]
        CW[CloudWatch<br/>Metrics & Alarms]
    end
    
    CF --> WAF
    WAF --> SHIELD
    SHIELD --> ALB
    
    ALB --> SG
    SG --> NACL
    NACL --> EC2
    EC2 --> RDS
    
    ALB --> FLOW
    WAF --> WAF_LOG
    FLOW --> CW
    WAF_LOG --> CW

    style CF fill:#e1f5fe
    style WAF fill:#ffebee
    style ALB fill:#fff3e0
    style EC2 fill:#c8e6c9
    style RDS fill:#c8e6c9

See: diagrams/08_integration_network_security.mmd

Diagram Explanation:
The network security integration diagram shows defense-in-depth with multiple security layers. The Edge Layer (blue/red) includes CloudFront for content delivery, WAF for application-layer protection, and Shield for DDoS protection. The VPC Layer (orange) includes an Application Load Balancer, security groups (stateful firewall), and NACLs (stateless firewall). The Application Layer (green) has EC2 instances and RDS databases in private subnets with no direct internet access. The Monitoring Layer logs all traffic with VPC Flow Logs and WAF logs, sending metrics to CloudWatch for alerting. This layered approach ensures attacks must bypass multiple security controls, and all traffic is logged for analysis.

Example Question Pattern:
"A company's web application is experiencing a DDoS attack. The application runs on EC2 instances behind an Application Load Balancer. What combination of services provides the MOST comprehensive protection?"

Solution Approach:

  1. DDoS Protection: Enable AWS Shield Advanced on ALB and CloudFront
  2. Application Protection: Deploy WAF with rate-limiting rules
  3. Network Protection: Use security groups to allow only ALB traffic to EC2
  4. Monitoring: Enable VPC Flow Logs and WAF logs for analysis
  5. Response: Configure CloudWatch alarms on request rate and error rate

Detailed Example: Securing a Multi-Tier Web Application
A company runs a three-tier web application: CloudFront → ALB → EC2 (application) → RDS (database). They implement: (1) CloudFront with WAF attached, blocking SQL injection and XSS attacks, (2) Custom origin with custom header verification ensuring traffic comes only from CloudFront, (3) ALB in public subnets with security group allowing HTTPS from CloudFront IP ranges, (4) EC2 instances in private subnets with security group allowing traffic only from ALB, (5) RDS in private subnets with security group allowing traffic only from EC2 security group, (6) NACLs on private subnets denying all inbound traffic from internet, (7) VPC endpoints for S3 and DynamoDB to avoid internet gateway, (8) VPC Flow Logs capturing all traffic for analysis, (9) Network Firewall inspecting traffic between subnets for malware. This architecture provides multiple layers of protection: edge protection, network segmentation, least privilege access, and comprehensive monitoring.

Scenario Type 4: Multi-Account Security Architecture

What it tests: Understanding of how Organizations, Control Tower, SCPs, and delegated administration work together.

How to approach:

  1. Account Structure: Design OU hierarchy (Security, Production, Development)
  2. Guardrails: Implement SCPs for security policies
  3. Centralized Logging: Aggregate logs in dedicated account
  4. Security Services: Use delegated administration for Security Hub, GuardDuty
  5. Compliance: Deploy Config rules organization-wide

Example Question Pattern:
"A company has 50 AWS accounts and needs to enforce that all S3 buckets are encrypted and all EC2 instances use approved AMIs. The solution must be centrally managed and cannot be bypassed. What is the MOST effective approach?"

Solution Approach:

  1. Organizations: Create organization with all 50 accounts
  2. SCPs: Create SCP denying s3:PutObject without encryption header
  3. Config: Deploy organization-wide Config rule for approved AMIs
  4. Remediation: Automatic remediation to terminate non-compliant instances
  5. Monitoring: Security Hub aggregates findings from all accounts

Detailed Example: Enterprise Multi-Account Security
An enterprise with 100 AWS accounts implements: (1) AWS Organizations with OUs: Security, Production, Development, Sandbox, (2) Control Tower landing zone with Log Archive and Audit accounts, (3) SCP on Production OU requiring encryption, MFA, and restricting regions, (4) SCP on Sandbox OU allowing all services for experimentation, (5) Delegated administrator account for Security Hub, GuardDuty, Macie, (6) Organization-wide CloudTrail sending logs to Log Archive account with Object Lock, (7) Config aggregator in Audit account showing compliance across all accounts, (8) Security Hub master-member relationship aggregating findings, (9) EventBridge rules in each account forwarding security events to central security account, (10) Lambda functions in security account for automated response. This architecture provides centralized security management, consistent policy enforcement, and comprehensive visibility across all accounts.


Advanced Topics

Topic 1: Threat Hunting with Detective and Athena

Prerequisites: Understanding of CloudTrail, VPC Flow Logs, GuardDuty

Why it's advanced: Requires correlating data across multiple log sources and understanding attacker techniques.

How to approach:

  1. Data Sources: Identify relevant logs (CloudTrail, VPC Flow Logs, DNS logs)
  2. Query Strategy: Use Athena for historical analysis, Detective for behavior graphs
  3. Indicators: Look for anomalies (unusual API calls, new IP addresses, privilege escalation)
  4. Timeline: Build timeline of attacker activity
  5. Impact Assessment: Determine what data was accessed or modified

Detailed Example: Investigating Potential Data Exfiltration
GuardDuty alerts on "Exfiltration:S3/ObjectRead.Unusual" - an IAM user downloaded an unusually large amount of data from S3. The security team investigates: (1) Use Detective to view the IAM user's behavior graph showing all API calls in the last 30 days, (2) Identify spike in s3:GetObject calls starting 3 days ago, (3) Use Athena to query CloudTrail logs for all S3 API calls by this user: SELECT eventtime, sourceipaddress, requestparameters FROM cloudtrail_logs WHERE useridentity.principalid = 'AIDAI...' AND eventname LIKE 'GetObject' ORDER BY eventtime, (4) Discover all downloads came from a new IP address in a foreign country, (5) Query VPC Flow Logs to see if data was transferred out: SELECT srcaddr, dstaddr, bytes FROM vpc_flow_logs WHERE srcaddr = '10.0.1.50' AND action = 'ACCEPT' ORDER BY bytes DESC, (6) Find large data transfer to external IP, (7) Revoke IAM user's credentials, (8) Enable MFA requirement for the user, (9) Implement S3 bucket policy requiring VPC endpoint for access. Investigation reveals the user's credentials were compromised and used to exfiltrate 50GB of data.

Topic 2: Compliance Automation with Config and Lambda

Prerequisites: Understanding of Config, Lambda, CloudFormation

Why it's advanced: Requires custom code and understanding of compliance requirements.

How to approach:

  1. Compliance Requirement: Define specific compliance rule
  2. Config Rule: Create custom Config rule with Lambda function
  3. Evaluation Logic: Implement logic to check compliance
  4. Remediation: Develop automated remediation
  5. Reporting: Generate compliance reports

Detailed Example: Enforcing Tag-Based Access Control
A company requires all resources to be tagged with "Owner", "Environment", and "CostCenter". They create a custom Config rule: (1) Lambda function receives resource configuration from Config, (2) Function checks if resource has all three required tags, (3) If tags missing, returns NON_COMPLIANT with details, (4) Config triggers remediation Lambda function, (5) Remediation function adds default tags or sends notification to resource owner, (6) Config aggregator shows compliance across all accounts, (7) Monthly report generated showing tag compliance by account and resource type. This ensures consistent tagging for cost allocation and access control.

Topic 3: Zero Trust Architecture on AWS

Prerequisites: Understanding of IAM, VPC, encryption, monitoring

Why it's advanced: Requires integrating multiple services and understanding zero trust principles.

Zero Trust Principles:

  1. Verify Explicitly: Always authenticate and authorize based on all available data points
  2. Least Privilege: Limit user access with just-in-time and just-enough-access
  3. Assume Breach: Minimize blast radius and segment access

Implementation on AWS:

  1. Identity: Use IAM Identity Center with MFA and conditional access
  2. Network: Implement micro-segmentation with security groups
  3. Data: Encrypt all data at rest and in transit
  4. Monitoring: Continuous monitoring with GuardDuty, Security Hub
  5. Automation: Automated response to security events

Detailed Example: Zero Trust for Sensitive Workload
A financial services company implements zero trust for their trading platform: (1) IAM Identity Center with MFA required for all users, (2) Session duration limited to 1 hour, (3) Conditional access policies based on IP address and device compliance, (4) VPC with micro-segmentation - each application tier in separate security group, (5) Security groups allow only required ports between tiers, (6) All data encrypted with KMS customer-managed keys, (7) VPC endpoints for all AWS services - no internet gateway, (8) Session Manager for EC2 access - no SSH keys or bastion hosts, (9) GuardDuty and Security Hub monitoring all activity, (10) Automated response to suspicious activity (isolate resources, revoke sessions), (11) All API calls logged to CloudTrail with log integrity validation, (12) Regular access reviews using IAM Access Analyzer. This architecture assumes no implicit trust and verifies every access request.


Common Question Patterns

Pattern 1: "Most Secure" Questions

How to recognize:

  • Question asks for "MOST secure" solution
  • Multiple options may work, but one is more secure

What they're testing:

  • Understanding of defense-in-depth
  • Knowledge of security best practices
  • Ability to prioritize security over convenience

How to answer:

  1. Eliminate options with obvious security flaws
  2. Look for options with multiple security layers
  3. Prefer customer-managed keys over AWS-managed
  4. Prefer private connectivity over public
  5. Prefer automated enforcement over manual processes

Example: "What is the MOST secure way to allow developers to access EC2 instances?"

  • ❌ SSH with password authentication
  • ❌ SSH with key pairs stored in S3
  • ✅ Session Manager with IAM authentication and MFA
  • ❌ Bastion host with SSH keys

Pattern 2: "Most Cost-Effective" Questions

How to recognize:

  • Question asks for "MOST cost-effective" or "LEAST expensive"
  • Security requirements are clearly stated

What they're testing:

  • Ability to balance security and cost
  • Knowledge of service pricing models
  • Understanding of when premium features are necessary

How to answer:

  1. Ensure solution meets all security requirements
  2. Compare service costs (Secrets Manager vs Parameter Store)
  3. Consider data transfer costs (VPN vs Direct Connect)
  4. Look for native AWS features over third-party
  5. Prefer serverless over always-on infrastructure

Example: "What is the MOST cost-effective way to rotate database credentials?"

  • ❌ Manual rotation by security team (operational cost)
  • ✅ Secrets Manager with automatic rotation (automated, but $0.40/secret/month)
  • ❌ Custom Lambda with Parameter Store (development cost)
  • ❌ Third-party secrets management tool (licensing cost)

Pattern 3: "Least Operational Overhead" Questions

How to recognize:

  • Question asks for "LEAST operational overhead" or "MOST operationally efficient"
  • Multiple solutions may work

What they're testing:

  • Preference for managed services over self-managed
  • Understanding of automation capabilities
  • Knowledge of AWS-native integrations

How to answer:

  1. Prefer managed services (RDS over EC2 database)
  2. Prefer automated solutions (Secrets Manager rotation)
  3. Prefer native integrations (GuardDuty over third-party)
  4. Avoid solutions requiring manual intervention
  5. Look for "set it and forget it" options

Example: "What provides the LEAST operational overhead for encrypting EBS volumes?"

  • ❌ Client-side encryption in application (requires code changes)
  • ❌ OS-level encryption (requires management)
  • ✅ EBS encryption with KMS (automatic, managed)
  • ❌ Third-party encryption software (requires installation and updates)

Section 5: Advanced Multi-Account Security Patterns

Centralized Security Operations

The Challenge: Managing security across hundreds of AWS accounts is complex. Each account has its own GuardDuty findings, Config rules, CloudTrail logs, and security configurations. Without centralization, security teams can't see the complete picture or respond effectively to threats.

The Solution: Implement a centralized security operations model using AWS Organizations, delegated administration, and aggregation services.

📊 Centralized Security Architecture:

graph TB
    subgraph "Management Account"
        ORG[AWS Organizations]
        SCPs[Service Control Policies]
    end
    
    subgraph "Security Account (Delegated Admin)"
        SH[Security Hub<br/>Aggregator]
        GD[GuardDuty<br/>Delegated Admin]
        CFG[Config<br/>Aggregator]
        CT[CloudTrail<br/>Organization Trail]
    end
    
    subgraph "Member Accounts"
        MA1[Account 1<br/>Findings]
        MA2[Account 2<br/>Findings]
        MA3[Account 3<br/>Findings]
    end
    
    ORG --> SCPs
    SCPs -.Enforce Policies.-> MA1
    SCPs -.Enforce Policies.-> MA2
    SCPs -.Enforce Policies.-> MA3
    
    MA1 --> SH
    MA2 --> SH
    MA3 --> SH
    
    MA1 --> GD
    MA2 --> GD
    MA3 --> GD
    
    MA1 --> CFG
    MA2 --> CFG
    MA3 --> CFG
    
    MA1 --> CT
    MA2 --> CT
    MA3 --> CT
    
    style ORG fill:#e1f5fe
    style SH fill:#c8e6c9
    style GD fill:#c8e6c9
    style CFG fill:#c8e6c9
    style CT fill:#c8e6c9

See: diagrams/08_integration_centralized_security_ops.mmd

Implementation Steps:

  1. Designate Security Account: Create a dedicated AWS account for security operations (separate from management account)

  2. Enable Delegated Administration:

    • GuardDuty: Designate security account as delegated administrator
    • Security Hub: Enable aggregation in security account
    • Config: Set up aggregator in security account
    • Macie: Designate delegated administrator for data discovery
  3. Configure Organization-Wide Services:

    • CloudTrail: Create organization trail in management account
    • Config: Deploy organization-wide Config rules
    • GuardDuty: Auto-enable for new accounts
  4. Implement SCPs: Enforce security baselines across all accounts

    • Prevent disabling of security services
    • Enforce encryption requirements
    • Restrict regions
    • Prevent root account usage
  5. Centralize Logging: All logs flow to security account S3 bucket

    • CloudTrail logs
    • VPC Flow Logs
    • GuardDuty findings
    • Config snapshots

Benefits:

  • Single pane of glass for security visibility
  • Consistent security policies across all accounts
  • Automated compliance checking
  • Faster incident response
  • Reduced operational overhead

Must Know: The management account should NOT be used for workloads or security operations. Use delegated administration to separate concerns.

Cross-Account Incident Response

Scenario: A GuardDuty finding in Account A (production) indicates a compromised EC2 instance. The security team operates from Account B (security account). How do you respond across accounts?

Solution Architecture:

  1. Detection (Account A):

    • GuardDuty detects suspicious activity
    • Finding sent to Security Hub in Account A
    • Security Hub forwards to aggregator in Account B
  2. Notification (Account B):

    • Security Hub aggregator receives finding
    • EventBridge rule triggers on high-severity findings
    • SNS sends alert to security team
    • Lambda function creates incident ticket
  3. Investigation (Cross-Account):

    • Security team assumes cross-account role into Account A
    • Detective analyzes behavior graph across accounts
    • CloudTrail logs reviewed in centralized S3 bucket
    • VPC Flow Logs analyzed with Athena
  4. Response (Account A):

    • Lambda function (triggered from Account B) isolates instance
    • Security group modified to block all traffic
    • EBS snapshot created for forensics
    • Instance tagged for investigation
  5. Remediation (Account A):

    • Systems Manager Automation document executed
    • Compromised instance terminated
    • Clean AMI launched from backup
    • Security group rules reviewed and tightened

Key Cross-Account Mechanisms:

  • IAM Roles: Security account assumes roles in member accounts
  • Resource Policies: S3 buckets allow cross-account access for logs
  • EventBridge: Cross-account event routing for automation
  • Detective: Behavior graph spans multiple accounts
  • Security Hub: Aggregates findings across accounts

💡 Tip: Use AWS Organizations to automatically create cross-account roles when new accounts are added. This ensures security team always has access for incident response.

Compliance Automation at Scale

The Challenge: Ensuring 100+ AWS accounts comply with security standards (CIS, PCI-DSS, HIPAA) requires continuous monitoring and automated remediation.

The Solution: Implement automated compliance checking and remediation using Config, Security Hub, and Systems Manager.

📊 Compliance Automation Flow:

sequenceDiagram
    participant Resource as AWS Resource
    participant Config as AWS Config
    participant EB as EventBridge
    participant SSM as Systems Manager
    participant SH as Security Hub
    participant Team as Security Team
    
    Resource->>Config: Configuration Change
    Config->>Config: Evaluate Rules
    Config->>Config: Non-Compliant
    Config->>EB: Compliance Change Event
    EB->>SSM: Trigger Automation
    SSM->>Resource: Remediate
    Resource->>Config: Configuration Updated
    Config->>Config: Re-evaluate
    Config->>SH: Update Compliance Status
    SH->>Team: Compliance Dashboard

See: diagrams/08_integration_compliance_automation_flow.mmd

Implementation Example - S3 Bucket Encryption:

  1. Config Rule: s3-bucket-server-side-encryption-enabled

    • Checks all S3 buckets for encryption
    • Evaluates on configuration changes
    • Marks non-compliant buckets
  2. EventBridge Rule: Triggers on non-compliant status

    {
      "source": ["aws.config"],
      "detail-type": ["Config Rules Compliance Change"],
      "detail": {
        "configRuleName": ["s3-bucket-server-side-encryption-enabled"],
        "newEvaluationResult": {
          "complianceType": ["NON_COMPLIANT"]
        }
      }
    }
    
  3. Systems Manager Automation: Enables encryption

    • Document: AWS-EnableS3BucketEncryption
    • Input: Bucket name from Config event
    • Action: Enable default encryption with KMS
  4. Verification: Config re-evaluates and marks compliant

  5. Reporting: Security Hub shows compliance status

Multi-Account Compliance:

  • Deploy Config rules organization-wide
  • Use conformance packs for standard compliance frameworks
  • Aggregate compliance data in security account
  • Generate compliance reports with Audit Manager

⚠️ Warning: Automated remediation can disrupt services if not tested. Start with detective controls (alerting) before implementing preventive controls (auto-remediation).

Data Residency and Sovereignty

The Challenge: Regulatory requirements (GDPR, data sovereignty laws) mandate that data must remain in specific geographic regions. How do you enforce this across multiple accounts and services?

The Solution: Implement multi-layered controls using SCPs, VPC endpoints, and monitoring.

Control Layers:

  1. Service Control Policies (Preventive):

    {
      "Version": "2012-10-17",
      "Statement": [{
        "Effect": "Deny",
        "Action": "*",
        "Resource": "*",
        "Condition": {
          "StringNotEquals": {
            "aws:RequestedRegion": ["eu-west-1", "eu-central-1"]
          }
        }
      }]
    }
    
    • Prevents any API calls outside allowed regions
    • Applies to all accounts in OU
    • Cannot be overridden by IAM policies
  2. VPC Endpoints (Network Control):

    • Use VPC endpoints for S3, DynamoDB
    • Prevents data from traversing internet
    • Endpoint policies restrict access to regional resources
  3. S3 Bucket Policies (Resource Control):

    {
      "Effect": "Deny",
      "Principal": "*",
      "Action": "s3:*",
      "Resource": "arn:aws:s3:::my-bucket/*",
      "Condition": {
        "StringNotEquals": {
          "aws:SourceRegion": "eu-west-1"
        }
      }
    }
    
  4. Monitoring (Detective):

    • CloudTrail logs all API calls with region
    • Config rules check resource locations
    • GuardDuty detects unusual cross-region activity
    • Athena queries for cross-region data transfers

Cross-Region Replication Considerations:

  • S3 CRR: Explicitly configured, logged in CloudTrail
  • RDS Read Replicas: Allowed for disaster recovery
  • DynamoDB Global Tables: Requires careful evaluation
  • CloudFront: Edge locations worldwide (evaluate if acceptable)

💡 Tip: Use AWS Organizations to create separate OUs for different regulatory requirements. Apply region-specific SCPs to each OU.


Section 6: Security Automation Patterns

Event-Driven Security Automation

Pattern: Automatically respond to security events without human intervention.

Common Automation Scenarios:

  1. Unauthorized API Call Detection:

    • CloudTrail logs API call
    • EventBridge detects unauthorized action
    • Lambda revokes credentials
    • SNS notifies security team
  2. Public S3 Bucket Remediation:

    • Config detects public bucket
    • EventBridge triggers remediation
    • Lambda removes public access
    • Security Hub updated
  3. Expired Certificate Rotation:

    • ACM certificate nearing expiration
    • EventBridge triggers 30 days before
    • Lambda requests new certificate
    • CloudFront distribution updated
  4. Compromised Instance Isolation:

    • GuardDuty detects malware
    • EventBridge triggers response
    • Lambda isolates instance (security group)
    • Step Functions orchestrates forensics

Best Practices:

  • Start with notifications, then add automation
  • Test automation in non-production first
  • Implement rollback mechanisms
  • Log all automated actions
  • Set up alerts for automation failures

Infrastructure as Code Security

Pattern: Embed security controls in infrastructure code to prevent misconfigurations.

CloudFormation Security Patterns:

  1. Encrypted Storage by Default:

    Resources:
      MyBucket:
        Type: AWS::S3::Bucket
        Properties:
          BucketEncryption:
            ServerSideEncryptionConfiguration:
              - ServerSideEncryptionByDefault:
                  SSEAlgorithm: AES256
          PublicAccessBlockConfiguration:
            BlockPublicAcls: true
            BlockPublicPolicy: true
            IgnorePublicAcls: true
            RestrictPublicBuckets: true
    
  2. Least Privilege IAM Roles:

    • Use managed policies where possible
    • Scope permissions to specific resources
    • Include conditions for additional restrictions
  3. Security Group Restrictions:

    • No 0.0.0.0/0 for SSH (port 22)
    • Use security group references instead of IPs
    • Document why each rule exists

Security Scanning:

  • Use cfn-nag to scan templates for security issues
  • Implement pre-commit hooks to check templates
  • Use Service Catalog to provide pre-approved templates
  • Enable CloudFormation drift detection

Secrets Management Automation

Pattern: Automatically rotate secrets and credentials without downtime.

Secrets Manager Rotation:

  1. RDS Database Credentials:

    • Secrets Manager stores master password
    • Lambda rotation function updates password
    • RDS updated with new password
    • Applications retrieve from Secrets Manager
    • Old password remains valid during rotation
  2. API Keys:

    • Secrets Manager stores API key
    • Lambda creates new key with provider
    • Old key marked for deletion (grace period)
    • Applications updated to use new key
    • Old key deleted after grace period
  3. SSH Keys:

    • EC2 Instance Connect generates temporary keys
    • Valid for 60 seconds
    • No permanent keys stored
    • All access logged in CloudTrail

Rotation Best Practices:

  • Rotate secrets every 30-90 days
  • Use automatic rotation for databases
  • Implement graceful rotation (both keys valid during transition)
  • Test rotation in non-production first
  • Monitor rotation failures

Section 7: Cost Optimization for Security

Balancing Security and Cost

The Challenge: Security services can be expensive. How do you maintain strong security while optimizing costs?

Cost Optimization Strategies:

  1. Right-Size Security Services:

    • GuardDuty: Costs based on CloudTrail events and VPC Flow Logs volume
      • Optimize: Reduce unnecessary logging, use S3 Intelligent-Tiering for logs
    • Security Hub: Costs based on findings ingested and compliance checks
      • Optimize: Disable unused security standards, filter low-priority findings
    • Macie: Costs based on S3 buckets scanned and data processed
      • Optimize: Scan only sensitive buckets, use sampling for large datasets
  2. Use Free Tier Services:

    • AWS Shield Standard: Free DDoS protection
    • AWS WAF: Pay only for rules and requests (no base fee)
    • CloudTrail: First trail free per region
    • Config: Free tier for first 1,000 rule evaluations
  3. Consolidate Logging:

    • Use S3 Lifecycle policies to transition logs to Glacier
    • Enable S3 Intelligent-Tiering for automatic cost optimization
    • Use CloudWatch Logs retention policies
    • Aggregate logs to reduce storage costs
  4. Automate Compliance:

    • Automated remediation reduces manual effort
    • Prevents costly security incidents
    • Reduces audit preparation time

Cost vs. Security Trade-offs:

Requirement Low Cost Option High Security Option Balanced Option
Secret Storage Parameter Store (free) Secrets Manager ($0.40/secret/month) Parameter Store for non-rotating, Secrets Manager for databases
DDoS Protection Shield Standard (free) Shield Advanced ($3,000/month) Shield Standard + WAF rate limiting
Vulnerability Scanning Manual scanning Inspector continuous scanning Inspector for critical workloads only
Log Retention 7 days CloudWatch 10 years S3 + Glacier 90 days CloudWatch, 7 years Glacier

💡 Tip: Security incidents are far more expensive than security services. A single data breach can cost millions. Invest in prevention.



Chapter Summary

What We Covered

  • Cross-Domain Scenarios: Incident response, data protection, network security, compliance integration
  • Advanced Topics: Zero trust architecture, multi-account security, hybrid cloud security
  • Question Patterns: "Most secure", "most cost-effective", "least operational overhead"

Critical Takeaways

  1. Defense in Depth: Combine multiple security controls across domains. No single control is sufficient.
  2. Incident Response Integration: GuardDuty detects → EventBridge triggers → Lambda/Step Functions respond → Detective investigates
  3. Data Protection Layers: Encryption in transit (TLS) + encryption at rest (KMS) + access control (IAM) + monitoring (CloudTrail)
  4. Network Security Layers: Edge (WAF/Shield) + VPC (Security Groups/NACLs) + Compute (host firewalls) + Monitoring (Flow Logs)
  5. Compliance Automation: Config detects → EventBridge triggers → Systems Manager remediates → Security Hub aggregates
  6. Zero Trust Principles: Never trust, always verify. Verify identity, device, location, and context for every access request.
  7. Multi-Account Security: Organizations for structure + Control Tower for automation + SCPs for guardrails + Config aggregator for visibility

Self-Assessment Checklist

Test yourself before moving on:

  • I can design a complete incident response workflow across multiple services
  • I understand how to implement defense in depth across all domains
  • I can explain zero trust architecture principles
  • I know how to secure multi-account environments
  • I can identify the "most secure" option in exam questions
  • I understand how to balance security, cost, and operational overhead
  • I can design hybrid cloud security architectures

Practice Questions

Try these from your practice test bundles:

  • Integration Bundle: Questions covering multiple domains
  • Full Practice Test 1: Complete 65-question exam simulation
  • Expected score: 75%+ to proceed

If you scored below 75%:

  • Review cross-domain integration patterns
  • Focus on understanding how services work together
  • Practice identifying question patterns (most secure, cost-effective, least overhead)

Quick Reference Card

Integration Patterns:

  • Incident Response: Detect (GuardDuty) → Trigger (EventBridge) → Respond (Lambda) → Investigate (Detective)
  • Data Protection: TLS + KMS + IAM + CloudTrail + S3 Object Lock
  • Network Security: WAF + Shield + Security Groups + NACLs + Network Firewall + Flow Logs
  • Compliance: Config + EventBridge + Systems Manager + Security Hub

Question Pattern Recognition:

  • "Most secure": Look for defense in depth, customer-managed keys, private connectivity, automated enforcement
  • "Most cost-effective": Meet security requirements with lowest cost service (Parameter Store vs Secrets Manager)
  • "Least operational overhead": Prefer managed services, automation, native integrations

Zero Trust Principles:

  1. Verify explicitly (authenticate and authorize every request)
  2. Use least privilege access (grant minimum required permissions)
  3. Assume breach (monitor, detect, respond)

Chapter 6 Complete

Next Chapter: 09_study_strategies - Study Strategies & Test-Taking Techniques


Section 3: Real-World Integration Scenarios

Introduction

The problem: The exam doesn't just test individual services - it tests your ability to design complete security solutions that integrate multiple services. Real-world scenarios require combining threat detection, logging, access control, data protection, and governance into cohesive architectures.

The solution: Understanding common integration patterns and how services work together enables you to design comprehensive security solutions. This section covers real-world scenarios that appear frequently on the exam.

Why it's tested: The Security Specialty exam emphasizes practical, real-world scenarios. You must demonstrate the ability to design end-to-end security solutions, not just understand individual services.

Common Integration Patterns

Pattern 1: Automated Incident Response Pipeline

Scenario: A company wants to automatically respond to security threats detected by GuardDuty.

Integration Architecture:

  1. Detection: GuardDuty detects a threat (e.g., compromised EC2 instance communicating with known malicious IP)
  2. Event Routing: GuardDuty sends finding to EventBridge
  3. Orchestration: EventBridge triggers Step Functions workflow
  4. Isolation: Step Functions invokes Lambda to isolate the instance (modify security group to deny all traffic)
  5. Snapshot: Lambda creates EBS snapshot for forensic analysis
  6. Notification: Lambda sends SNS notification to security team
  7. Investigation: Security team uses Detective to investigate the incident
  8. Logging: All actions are logged to CloudTrail and Security Hub

Services Integrated: GuardDuty, EventBridge, Step Functions, Lambda, EC2, SNS, Detective, CloudTrail, Security Hub

Key Exam Points:

  • EventBridge is the glue for event-driven security automation
  • Step Functions orchestrates multi-step remediation workflows
  • Lambda executes remediation actions (isolate, snapshot, notify)
  • Detective provides investigation capabilities
  • Security Hub aggregates findings from multiple sources

Detailed Example: A GuardDuty finding "UnauthorizedAccess:EC2/MaliciousIPCaller.Custom" is generated for instance i-1234567890abcdef0. EventBridge rule matches the finding and triggers a Step Functions workflow. The workflow: (1) Invokes Lambda to modify the instance's security group, removing all inbound/outbound rules except SSH from the security team's IP. (2) Invokes Lambda to create an EBS snapshot of the instance's volumes for forensic analysis. (3) Invokes Lambda to tag the instance with "Status=Quarantined" and "Incident=INC-2024-001". (4) Sends SNS notification to the security team with incident details. (5) Creates a Security Hub finding with "CRITICAL" severity. The entire workflow completes in under 2 minutes, containing the threat before it can spread.

Pattern 2: Multi-Account Security Baseline Deployment

Scenario: A company wants to deploy security baselines to 50 AWS accounts automatically.

Integration Architecture:

  1. Organization Setup: AWS Organizations with OUs for Dev, Test, Prod
  2. Landing Zone: Control Tower creates landing zone with security/logging accounts
  3. Guardrails: Control Tower applies mandatory guardrails (SCPs + Config rules)
  4. Baseline Deployment: CloudFormation StackSets deploy security baseline to all accounts
  5. Monitoring: Security Hub aggregates findings from all accounts
  6. Compliance: Config aggregator provides multi-account compliance view
  7. Logging: Organization trail sends CloudTrail logs to central S3 bucket
  8. Alerting: EventBridge in each account forwards security events to central account

Services Integrated: Organizations, Control Tower, CloudFormation StackSets, Security Hub, Config, CloudTrail, EventBridge, S3

Key Exam Points:

  • Control Tower automates multi-account governance
  • StackSets deploy resources to multiple accounts simultaneously
  • Security Hub aggregator provides centralized security view
  • Config aggregator provides centralized compliance view
  • Organization trail logs all accounts to central location

Detailed Example: A company enables Control Tower, which creates a landing zone with management, security, and logging accounts. They create OUs for Development (10 accounts), Testing (5 accounts), and Production (35 accounts). They attach SCPs to each OU: Development OU allows all regions, Testing OU restricts to us-east-1 and us-west-2, Production OU restricts to us-east-1 only. They create a CloudFormation StackSet with security baseline: GuardDuty enabled, Security Hub enabled, Config enabled with 20 managed rules, CloudWatch log group for VPC Flow Logs. They deploy the StackSet to all 50 accounts across all OUs. Within 30 minutes, all accounts have the security baseline deployed. Security Hub aggregator in the security account shows findings from all 50 accounts. Config aggregator shows compliance status for all accounts. The company achieved consistent security across all accounts with minimal manual effort.

Pattern 3: Data Protection with Encryption and Access Control

Scenario: A company wants to ensure sensitive data in S3 is encrypted, access-controlled, and audited.

Integration Architecture:

  1. Encryption: S3 bucket encrypted with KMS customer-managed key
  2. Access Control: S3 bucket policy restricts access to specific IAM roles
  3. Key Policy: KMS key policy restricts key usage to authorized principals
  4. Logging: S3 access logging enabled, logs sent to separate bucket
  5. Monitoring: CloudTrail logs all S3 API calls
  6. Data Discovery: Macie scans bucket for sensitive data (PII, credentials)
  7. Compliance: Config rule checks bucket encryption and public access settings
  8. Alerting: EventBridge triggers Lambda when Macie finds sensitive data
  9. Immutability: S3 Object Lock prevents deletion of critical data

Services Integrated: S3, KMS, IAM, CloudTrail, Macie, Config, EventBridge, Lambda, S3 Object Lock

Key Exam Points:

  • KMS customer-managed keys provide granular access control
  • S3 bucket policies and KMS key policies work together for defense-in-depth
  • Macie automatically discovers sensitive data
  • Config ensures compliance with encryption requirements
  • S3 Object Lock provides immutability for compliance

Detailed Example: A financial services company stores customer financial records in S3. They create a KMS customer-managed key with a key policy allowing only the "DataProcessing" IAM role to use the key. They create an S3 bucket with default encryption using the KMS key. They create a bucket policy allowing s3:GetObject and s3:PutObject only from the DataProcessing role and only if the request uses the specific KMS key. They enable S3 access logging to a separate audit bucket. They enable CloudTrail data events for the bucket. They enable Macie to scan the bucket daily for PII. They create a Config rule to ensure the bucket has encryption enabled and public access blocked. They enable S3 Object Lock in compliance mode with 7-year retention for regulatory compliance. When a developer attempts to access the bucket without using the DataProcessing role, the request is denied by the bucket policy. When Macie finds a file containing unencrypted credit card numbers, it generates a finding and EventBridge triggers a Lambda function to quarantine the file. The company achieved comprehensive data protection with multiple layers of security.

Pattern 4: Network Security with Defense-in-Depth

Scenario: A company wants to protect a web application with multiple layers of network security.

Integration Architecture:

  1. Edge Protection: CloudFront with WAF (OWASP Top 10 rules)
  2. DDoS Protection: Shield Advanced on CloudFront and ALB
  3. Load Balancer: ALB with WAF (rate limiting, geo-blocking)
  4. VPC Security: Security groups (stateful) and NACLs (stateless)
  5. Network Firewall: Centralized firewall with IDS/IPS
  6. Private Connectivity: VPC endpoints for AWS services (no internet)
  7. Monitoring: VPC Flow Logs, WAF logs, Network Firewall logs
  8. Analysis: Athena queries on logs for threat hunting
  9. Alerting: CloudWatch alarms on suspicious patterns

Services Integrated: CloudFront, WAF, Shield, ALB, VPC, Security Groups, NACLs, Network Firewall, VPC Endpoints, VPC Flow Logs, Athena, CloudWatch

Key Exam Points:

  • Defense-in-depth uses multiple layers of security
  • WAF at CloudFront and ALB provides redundant protection
  • Network Firewall provides deep packet inspection
  • VPC endpoints keep traffic off the internet
  • Comprehensive logging enables threat detection

Detailed Example: A company deploys a web application with defense-in-depth. Internet traffic hits CloudFront, which has WAF rules blocking SQL injection and XSS attacks. Shield Advanced protects CloudFront from DDoS attacks. CloudFront forwards requests to an ALB, which has additional WAF rules for rate limiting (max 2,000 requests per 5 minutes per IP) and geo-blocking (block traffic from high-risk countries). The ALB is in a public subnet with a security group allowing only ports 80/443 from CloudFront. The ALB forwards requests to EC2 instances in private subnets. The EC2 security group allows traffic only from the ALB security group. A Network Firewall is deployed in a dedicated subnet, inspecting all traffic with Suricata rules to detect malware and command-and-control traffic. EC2 instances access S3 and DynamoDB through VPC endpoints, keeping traffic within AWS. VPC Flow Logs, WAF logs, and Network Firewall logs are sent to S3. Athena queries analyze logs daily for suspicious patterns. CloudWatch alarms alert on high error rates or blocked requests. This architecture provides multiple layers of protection, ensuring that if one layer is bypassed, others still protect the application.

Pattern 5: Compliance Automation and Continuous Monitoring

Scenario: A company must maintain PCI-DSS compliance and prove it continuously.

Integration Architecture:

  1. Compliance Framework: Audit Manager with PCI-DSS framework
  2. Configuration Monitoring: Config with PCI-DSS conformance pack
  3. Vulnerability Scanning: Inspector scans EC2 and containers
  4. Security Findings: Security Hub aggregates findings
  5. Automated Remediation: EventBridge triggers Lambda for auto-remediation
  6. Evidence Collection: Audit Manager collects evidence from Config, CloudTrail, Security Hub
  7. Reporting: Audit Manager generates audit-ready reports
  8. Alerting: SNS notifications for non-compliance

Services Integrated: Audit Manager, Config, Inspector, Security Hub, EventBridge, Lambda, CloudTrail, SNS

Key Exam Points:

  • Audit Manager automates compliance evidence collection
  • Config conformance packs provide pre-built compliance rules
  • Security Hub provides centralized compliance view
  • Automated remediation reduces time to compliance
  • Continuous monitoring proves ongoing compliance

Detailed Example: A payment processing company must maintain PCI-DSS compliance. They create an Audit Manager assessment using the PCI-DSS framework. They deploy the Config PCI-DSS conformance pack, which includes 30+ Config rules checking for encryption, access controls, logging, and network security. They enable Inspector to scan all EC2 instances and container images for vulnerabilities. They enable Security Hub with PCI-DSS standard. Config rules continuously monitor compliance: "s3-bucket-server-side-encryption-enabled" ensures all S3 buckets are encrypted, "cloudtrail-enabled" ensures CloudTrail is logging, "iam-password-policy" ensures strong password requirements. When a developer creates an unencrypted S3 bucket, Config detects non-compliance within minutes. EventBridge triggers a Lambda function that enables encryption on the bucket. The remediation is logged to CloudTrail. Audit Manager collects evidence of the non-compliance and remediation. Security Hub shows the compliance status improving from 95% to 100%. Audit Manager generates a report showing all PCI-DSS requirements are met, with evidence from Config, CloudTrail, and Security Hub. The company provides the report to their auditor, demonstrating continuous compliance.

Cross-Domain Decision Framework

When designing security solutions, consider these factors:

  1. Threat Detection: Which services detect threats? (GuardDuty, Macie, Inspector, Security Hub)
  2. Logging: What needs to be logged? (CloudTrail, VPC Flow Logs, S3 access logs, WAF logs)
  3. Access Control: Who can access what? (IAM, SCPs, resource policies, security groups)
  4. Data Protection: How is data protected? (KMS, S3 encryption, TLS, VPN)
  5. Monitoring: How do you know what's happening? (CloudWatch, Security Hub, Config)
  6. Response: How do you respond to threats? (EventBridge, Lambda, Step Functions)
  7. Compliance: How do you prove compliance? (Config, Audit Manager, CloudTrail)

Exam Strategy: When you see a scenario question, identify which of these 7 areas are involved and select services that address each area.

Common Exam Traps

Trap 1: Choosing a single service when multiple are needed

  • ❌ Wrong: "Use WAF to protect against all attacks"
  • ✅ Correct: "Use WAF for application-layer attacks, Shield for DDoS, and Network Firewall for network-layer threats"

Trap 2: Forgetting about logging and monitoring

  • ❌ Wrong: "Deploy GuardDuty to detect threats" (but no response mechanism)
  • ✅ Correct: "Deploy GuardDuty, send findings to EventBridge, trigger Lambda for automated response, log to CloudTrail"

Trap 3: Not considering least privilege

  • ❌ Wrong: "Grant s3:* permissions to the application role"
  • ✅ Correct: "Grant only s3:GetObject and s3:PutObject on specific bucket ARNs"

Trap 4: Ignoring encryption

  • ❌ Wrong: "Store sensitive data in S3"
  • ✅ Correct: "Store sensitive data in S3 with KMS encryption, bucket policy requiring encryption, and Macie scanning for unencrypted data"

Trap 5: Not using defense-in-depth

  • ❌ Wrong: "Use security groups to control access"
  • ✅ Correct: "Use security groups, NACLs, WAF, and Network Firewall for layered defense"

Chapter Summary

What We Covered

This chapter covered integration and advanced topics, including:

  • Cross-Domain Scenarios: Multi-service architectures, end-to-end security
  • Security Automation: EventBridge, Lambda, Step Functions, automated response
  • Hybrid Security: On-premises integration, VPN, Direct Connect
  • Zero Trust Architecture: Verify explicitly, least privilege, assume breach
  • DevSecOps: Security in CI/CD, automated scanning, shift-left
  • Multi-Region Security: Global architectures, cross-region replication
  • Cost Optimization: Security cost management, rightsizing

Critical Takeaways

  1. Defense in Depth: Layer multiple security controls across all domains
  2. Automation: Use EventBridge + Lambda for automated security responses
  3. Zero Trust: Never trust, always verify, least privilege everywhere
  4. Integration: Security services work together (GuardDuty → Security Hub → EventBridge → Lambda)
  5. Hybrid: Secure on-premises connectivity with VPN or Direct Connect
  6. Multi-Region: Replicate security controls across regions
  7. DevSecOps: Integrate security into CI/CD pipelines

Self-Assessment Checklist

Test yourself before moving on:

  • I can design end-to-end security architectures
  • I understand how to integrate multiple security services
  • I know how to automate security responses
  • I can design hybrid cloud security
  • I understand zero trust principles
  • I know how to implement DevSecOps
  • I can design multi-region security
  • I understand security cost optimization

Practice Questions

Try these from your practice test bundles:

  • Full Practice Test 1: Questions 1-50 (All domains)
  • Full Practice Test 2: Questions 1-50 (All domains)
  • Full Practice Test 3: Questions 1-50 (All domains)
  • Expected score: 80%+ to proceed

If you scored below 80%:

  • Review weak domains identified in practice tests
  • Focus on: Integration patterns, automation, cross-domain scenarios

Quick Reference Card

Integration Patterns:

  • Threat Detection: GuardDuty → Security Hub → EventBridge → Lambda
  • Compliance: Config → Security Hub → Audit Manager
  • Incident Response: Detective → EventBridge → Step Functions → Systems Manager
  • Data Protection: Macie → EventBridge → Lambda → S3 Object Lock

Security Layers:

  1. Identity: IAM, Cognito, IAM Identity Center
  2. Network: VPC, security groups, NACLs, Network Firewall
  3. Edge: WAF, Shield, CloudFront
  4. Compute: EC2 hardening, patching, IAM roles
  5. Data: KMS, S3 encryption, TLS
  6. Monitoring: CloudTrail, CloudWatch, VPC Flow Logs
  7. Response: EventBridge, Lambda, Step Functions

Exam Strategy:

  • Identify all security requirements in the scenario
  • Select services that address each requirement
  • Prefer AWS-managed services
  • Choose automated solutions
  • Implement defense in depth
  • Follow least privilege
  • Enable logging and monitoring

Chapter 7 Complete

Next Chapter: 09_study_strategies - Study Strategies and Test-Taking Techniques


Chapter Summary

What We Covered

This chapter explored cross-domain integration scenarios that combine concepts from multiple domains:

Complete Security Architecture: Designing end-to-end security architectures that integrate threat detection, logging, network security, IAM, data protection, and governance.

Incident Response Integration: Coordinating incident response across multiple security services and domains, from detection through investigation to remediation and recovery.

Compliance Automation: Automating compliance monitoring and evidence collection across all security domains using Config, Security Hub, and Audit Manager.

Multi-Region Security: Implementing security controls across multiple AWS regions with centralized management and monitoring.

Hybrid Security: Securing hybrid architectures that span on-premises and AWS environments with consistent security policies.

Zero Trust Architecture: Implementing zero trust principles across all domains with identity-based access, continuous verification, and least privilege.

DevSecOps Integration: Integrating security into CI/CD pipelines with automated security testing, vulnerability scanning, and compliance checks.

Cost-Optimized Security: Balancing security requirements with cost optimization through right-sizing, automation, and efficient resource usage.

Critical Takeaways

  1. Security is Holistic: Effective security requires integration across all domains. Threat detection without logging is blind, IAM without network security is incomplete, and data protection without governance is unmanageable.

  2. Automation is Essential: Manual security operations don't scale. Automate detection (GuardDuty), response (EventBridge + Lambda), compliance (Config), and evidence collection (Audit Manager).

  3. Defense in Depth: Layer security controls across all domains. Edge security (WAF, Shield) + network security (security groups, NACLs) + compute security (patching, hardening) + data protection (encryption) + IAM (least privilege) + governance (SCPs).

  4. Centralize Management: Use multi-account strategies with centralized security management (Security Hub aggregation, delegated administration, organization trails) for visibility and control.

  5. Continuous Compliance: Compliance is not a point-in-time activity. Use Config rules, Security Hub standards, and Audit Manager for continuous compliance monitoring and automated evidence collection.

  6. Zero Trust Principles: Never trust, always verify. Use identity-based access (IAM), encrypt everything (data at rest and in transit), implement least privilege (IAM policies, security groups), and continuously monitor (CloudTrail, VPC Flow Logs).

  7. Incident Response Readiness: Prepare for incidents before they happen. Have playbooks, automate response workflows, practice with game days, and ensure forensic capabilities (logging, snapshots, isolation).

  8. Cost-Aware Security: Security doesn't have to be expensive. Use AWS managed services (GuardDuty, Security Hub), automate operations (reduce manual work), right-size resources (Trusted Advisor), and optimize logging (lifecycle policies).

Self-Assessment Checklist

Test yourself before moving on:

  • I can design complete security architectures integrating all six domains
  • I understand how to coordinate incident response across multiple services
  • I can automate compliance monitoring and evidence collection
  • I know how to implement multi-region security with centralized management
  • I can secure hybrid architectures spanning on-premises and AWS
  • I understand zero trust principles and how to implement them in AWS
  • I can integrate security into DevSecOps pipelines
  • I know how to optimize security costs without compromising protection
  • I can design automated security workflows using EventBridge, Lambda, and Step Functions
  • I understand how to centralize security management in multi-account environments
  • I can implement defense in depth across all security layers
  • I know how to balance security, cost, and operational complexity

Practice Questions

Try these from your practice test bundles:

  • Full Practice Test Bundle 1: All 50 questions (Exam-realistic, all domains)
  • Full Practice Test Bundle 2: All 50 questions (Different questions, all domains)
  • Full Practice Test Bundle 3: All 50 questions (Final practice, all domains)
  • Expected score: 75%+ to pass (equivalent to 750/1000 on real exam)

If you scored below 75%:

  • Review weak domains identified in practice tests
  • Focus on cross-domain scenarios (incident response, compliance automation)
  • Practice designing complete security architectures
  • Study integration patterns between security services

Quick Reference Card

Integration Patterns:

  • Detection → Investigation → Response: GuardDuty → Detective → Lambda/Step Functions
  • Logging → Analysis → Alerting: CloudTrail → Athena → CloudWatch Alarms
  • Compliance → Remediation: Config → Config Remediation → Systems Manager
  • Threat → Isolation → Forensics: GuardDuty → Lambda (isolation) → Snapshots (forensics)

Cross-Domain Scenarios:

  • Data Breach Response: GuardDuty detects exfiltration → Detective investigates → Lambda isolates resources → Macie identifies sensitive data → Athena analyzes CloudTrail → Security Hub aggregates findings
  • Compliance Audit: Config monitors configurations → Security Hub checks standards → Audit Manager collects evidence → Macie classifies data → CloudTrail provides audit logs
  • Multi-Account Security: Organizations provides structure → Control Tower applies guardrails → Security Hub aggregates findings → CloudTrail organization trail logs all accounts → Delegated administration centralizes management

Security Architecture Layers:

  1. Edge Layer: CloudFront, WAF, Shield, Route 53
  2. Network Layer: VPC, security groups, NACLs, Network Firewall
  3. Compute Layer: EC2 hardening, patching, IAM roles, Inspector
  4. Data Layer: Encryption (KMS), S3 Object Lock, Secrets Manager
  5. Identity Layer: IAM, IAM Identity Center, Cognito, MFA
  6. Governance Layer: Organizations, Control Tower, Config, Security Hub

Automation Framework:

  • Detection: GuardDuty, Security Hub, Config, Macie, Inspector
  • Orchestration: EventBridge, Step Functions
  • Execution: Lambda, Systems Manager
  • Notification: SNS, EventBridge
  • Storage: S3, DynamoDB
  • Analysis: Athena, CloudWatch Logs Insights, Detective

Exam Tips:

  • Cross-domain questions test your ability to integrate multiple services
  • Look for scenarios that require coordination between detection, investigation, and response
  • Understand how to centralize security in multi-account environments
  • Know when to use each security service and how they work together
  • Practice designing complete security architectures, not just individual components
  • Remember that automation is key to scalable security operations


Chapter Summary

What We Covered

This chapter explored how to integrate security concepts across multiple domains:

Cross-Domain Security Scenarios

  • Incident response workflows combining threat detection, logging, and remediation
  • Network security architectures integrating edge, network, and compute controls
  • Data protection strategies combining encryption, access control, and lifecycle management
  • Compliance automation integrating Config, Security Hub, and Audit Manager
  • Multi-region security architectures for disaster recovery and resilience

Advanced Security Patterns

  • Zero Trust architecture implementation in AWS
  • DevSecOps pipeline integration with security scanning and compliance checks
  • Centralized security operations center (SOC) architecture
  • Hybrid cloud security for AWS and on-premises integration
  • Cost optimization while maintaining security posture

Real-World Security Architectures

  • Complete security architecture for regulated industries (healthcare, finance)
  • Multi-account security strategy for enterprises
  • Serverless application security patterns
  • Container security with ECS/EKS
  • Data lake security architecture

Critical Takeaways

  1. Security is layered: Combine controls from multiple domains for defense in depth
  2. Automate everything: Use EventBridge, Lambda, and Step Functions to automate security responses
  3. Centralize visibility: Aggregate findings in Security Hub and logs in centralized S3 buckets
  4. Assume breach: Design architectures assuming compromise will occur, focus on detection and response
  5. Zero Trust principles: Never trust, always verify - authenticate and authorize every request
  6. Compliance as code: Use Config rules and CloudFormation to enforce compliance automatically
  7. Least privilege everywhere: Apply least privilege to IAM, security groups, and resource policies
  8. Encrypt everything: Encrypt data at rest and in transit across all services
  9. Monitor continuously: Use GuardDuty, Config, and CloudWatch for continuous monitoring
  10. Test regularly: Conduct regular security assessments, penetration tests, and Well-Architected reviews

Integration Patterns

Incident Response Integration:

  • GuardDuty finding → EventBridge → Lambda → Isolate resource + SNS notification + Detective investigation
  • Config non-compliance → EventBridge → Systems Manager Automation → Remediate + Security Hub finding
  • CloudWatch alarm → SNS → Lambda → Step Functions workflow → Multi-step remediation

Data Protection Integration:

  • S3 bucket → Macie scan → Finding → EventBridge → Lambda → Update bucket policy + Encrypt
  • RDS instance → Secrets Manager → Automatic rotation → CloudWatch alarm on failure
  • KMS key → CloudTrail → CloudWatch Logs → Metric filter → Alarm on unauthorized usage

Network Security Integration:

  • CloudFront → WAF → ALB → Security groups → EC2 instances (layered defense)
  • VPC → Flow Logs → S3 → Athena → QuickSight dashboard (traffic analysis)
  • Transit Gateway → Network Firewall → VPC endpoints → Private connectivity

Compliance Integration:

  • Organizations → Control Tower → Config rules → Security Hub → Audit Manager
  • CloudFormation → Drift detection → EventBridge → Lambda → Notification
  • Macie → S3 findings → Security Hub → Compliance dashboard

Self-Assessment Checklist

Test yourself on integration scenarios:

Cross-Domain Understanding:

  • I can design complete security architectures combining multiple domains
  • I understand how different security services integrate and complement each other
  • I can troubleshoot issues that span multiple security domains
  • I know how to automate security workflows across services

Advanced Patterns:

  • I can design Zero Trust architectures in AWS
  • I understand how to integrate security into DevOps pipelines
  • I can design centralized security operations architectures
  • I know how to secure hybrid cloud environments

Real-World Application:

  • I can design security for regulated industries (HIPAA, PCI-DSS)
  • I understand multi-account security strategies for enterprises
  • I can secure serverless and container workloads
  • I know how to balance security with cost optimization

Practice Questions

Try these from your practice test bundles:

  • Full Practice Test 1: Questions 1-50 (Exam-realistic, all domains)
  • Full Practice Test 2: Questions 1-50 (Different questions, all domains)
  • Full Practice Test 3: Questions 1-50 (Final practice, all domains)

Expected score: 80%+ to be exam-ready

If you scored below 80%:

  • Review weak domains identified in practice tests
  • Focus on integration scenarios that combine multiple services
  • Practice troubleshooting workflows that span multiple domains
  • Review decision frameworks for service selection

Quick Reference Card

Integration Principles:

  • Defense in Depth: Multiple layers of security controls
  • Automation: EventBridge + Lambda/Step Functions for automated response
  • Centralization: Security Hub for findings, S3 for logs, Organizations for accounts
  • Least Privilege: IAM policies, security groups, resource policies
  • Encryption: KMS for keys, TLS for transit, service-native for rest
  • Monitoring: GuardDuty + Config + CloudWatch for continuous monitoring

Common Integration Patterns:

  • Detection → Response → Remediation → Notification
  • Compliance → Monitoring → Alerting → Remediation
  • Data → Classification → Protection → Lifecycle
  • Network → Segmentation → Filtering → Monitoring

Service Combinations:

  • Threat Detection: GuardDuty + Security Hub + Detective + Macie
  • Logging: CloudTrail + VPC Flow Logs + CloudWatch Logs + S3
  • Network Security: WAF + Shield + Network Firewall + Security Groups
  • IAM: IAM Identity Center + Cognito + STS + Organizations
  • Data Protection: KMS + Secrets Manager + S3 encryption + RDS encryption
  • Governance: Organizations + Control Tower + Config + Service Catalog

Automation Workflows:

  1. Automated Incident Response:
    • GuardDuty → EventBridge → Lambda → Isolate + Notify + Investigate
  2. Automated Compliance:
    • Config → Non-compliance → EventBridge → Systems Manager → Remediate
  3. Automated Data Protection:
    • Macie → Sensitive data → EventBridge → Lambda → Encrypt + Restrict access
  4. Automated Patching:
    • Inspector → Vulnerability → EventBridge → Systems Manager → Patch

You've completed all domain chapters! You're now ready for the final preparation phase.


  1. Automated Compliance:
    • Config → Non-compliance → EventBridge → Systems Manager → Remediate
  2. Data Protection:
    • Macie → Sensitive data found → EventBridge → Lambda → Encrypt + Notify
  3. Multi-Account Security:
    • Organizations + Control Tower + Security Hub + Config Aggregator → Centralized visibility

Cross-Domain Decision Framework:

  1. Identify the requirement (threat detection, compliance, data protection, etc.)
  2. Select primary service (GuardDuty, Config, Macie, etc.)
  3. Add supporting services (CloudTrail for logs, KMS for encryption, etc.)
  4. Implement automation (EventBridge + Lambda for response)
  5. Centralize visibility (Security Hub for aggregation)
  6. Monitor and improve (CloudWatch for metrics, Trusted Advisor for recommendations)

Chapter Summary

What We Covered

This chapter demonstrated how all six domains of the SCS-C02 exam work together in real-world scenarios. We explored:

Cross-Domain Integration Patterns

  • How threat detection (Domain 1) relies on logging (Domain 2) and triggers automated responses
  • How network security (Domain 3) is controlled by IAM policies (Domain 4)
  • How data protection (Domain 5) is enforced through governance policies (Domain 6)
  • How all domains converge in Security Hub for centralized visibility

Common Exam Scenarios

  • Automated incident response workflows combining GuardDuty, EventBridge, Lambda, and Systems Manager
  • Compliance automation using Config, Security Hub, and automated remediation
  • Data protection strategies combining Macie, KMS, S3 encryption, and lifecycle policies
  • Multi-account security architectures using Organizations, Control Tower, and centralized logging

Service Combinations

  • Threat Detection: GuardDuty + Security Hub + Detective + Macie
  • Logging: CloudTrail + VPC Flow Logs + CloudWatch Logs + S3
  • Network Security: WAF + Shield + Network Firewall + Security Groups
  • IAM: IAM Identity Center + Cognito + STS + Organizations
  • Data Protection: KMS + Secrets Manager + S3 encryption + RDS encryption
  • Governance: Organizations + Control Tower + Config + Service Catalog

Automation Workflows

  • Detection → Response → Remediation → Notification
  • Compliance → Monitoring → Alerting → Remediation
  • Data → Classification → Protection → Lifecycle
  • Network → Segmentation → Filtering → Monitoring

Critical Takeaways

  1. Security Hub is the Integration Point: Security Hub aggregates findings from all security services and provides a unified view. It's the central hub for cross-domain security.

  2. EventBridge Enables Automation: EventBridge connects security services to automated response workflows. Use it to trigger Lambda functions, Step Functions, or Systems Manager runbooks.

  3. CloudTrail is the Foundation: CloudTrail logs all API activity and feeds into GuardDuty, Detective, and Athena. Without CloudTrail, you have no visibility.

  4. Defense in Depth Requires All Domains: Effective security requires layering controls across all six domains - edge security, network security, compute security, IAM, data protection, and governance.

  5. Automation is Essential: Manual security operations don't scale in the cloud. Automate detection, response, and remediation using EventBridge, Lambda, and Systems Manager.

  6. Multi-Account is the Standard: Enterprise security requires multi-account architectures with Organizations, Control Tower, and centralized logging. Single-account architectures don't scale.

  7. Compliance is Continuous: Use Config rules, Security Hub standards, and Audit Manager for continuous compliance monitoring. Don't rely on point-in-time audits.

  8. Zero Trust Requires All Domains: Zero trust architecture requires identity verification (Domain 4), network segmentation (Domain 3), data encryption (Domain 5), and continuous monitoring (Domains 1-2).

Self-Assessment Checklist

Test yourself on cross-domain scenarios. You should be able to:

Automated Incident Response:

  • Design a workflow that detects threats (GuardDuty), investigates (Detective), isolates (Lambda), and notifies (SNS)
  • Explain how CloudTrail logs feed into GuardDuty for threat detection
  • Implement automated remediation using EventBridge and Systems Manager
  • Centralize findings from multiple accounts using Security Hub

Compliance Automation:

  • Design a compliance monitoring solution using Config rules and Security Hub standards
  • Implement automated remediation for non-compliant resources
  • Collect evidence for audits using Audit Manager
  • Enforce compliance policies across accounts using SCPs and Firewall Manager

Data Protection:

  • Design a data protection strategy combining Macie (discovery), KMS (encryption), and S3 Object Lock (retention)
  • Implement automated encryption for sensitive data discovered by Macie
  • Enforce encryption policies using SCPs and bucket policies
  • Manage data lifecycle across multiple storage classes

Multi-Account Security:

  • Design a multi-account architecture using Organizations and Control Tower
  • Implement centralized logging to a dedicated logging account
  • Aggregate security findings using Security Hub and Config aggregators
  • Enforce account-level restrictions using SCPs

Network Security:

  • Design a layered network security architecture (WAF, Shield, Network Firewall, security groups)
  • Implement private connectivity using VPC endpoints and PrivateLink
  • Monitor network traffic using VPC Flow Logs and Traffic Mirroring
  • Troubleshoot connectivity issues using VPC Reachability Analyzer

Decision-Making:

  • Choose the right combination of services for different security scenarios
  • Determine the order of implementation for security controls
  • Identify gaps in security architectures and recommend improvements
  • Balance security, cost, and operational complexity

Practice Questions

Try these from your practice test bundles:

  • Full Practice Test 1: All 50 questions (tests cross-domain understanding)
  • Full Practice Test 2: All 50 questions (different scenarios)
  • Full Practice Test 3: All 50 questions (advanced scenarios)
  • Service-Focused Bundles: Test understanding of how services work together

Expected Score: 75%+ to be exam-ready

If you scored below 75%:

  • Review sections:
    • Automated Incident Response (if you struggled with workflow questions)
    • Multi-Account Security (if you struggled with Organizations/Control Tower questions)
    • Data Protection Strategies (if you struggled with encryption and lifecycle questions)
    • Network Security Layers (if you struggled with defense-in-depth questions)
  • Focus on:
    • Understanding how services integrate (EventBridge, Security Hub, CloudTrail)
    • Practicing cross-domain scenarios that combine multiple services
    • Memorizing common automation patterns (detection → response → remediation)
    • Understanding the order of implementation for security controls

Quick Reference Card

Common Integration Patterns:

  • Detection → Response → Remediation → Notification
  • Compliance → Monitoring → Alerting → Remediation
  • Data → Classification → Protection → Lifecycle
  • Network → Segmentation → Filtering → Monitoring

Service Combinations:

  • Threat Detection: GuardDuty + Security Hub + Detective + Macie
  • Logging: CloudTrail + VPC Flow Logs + CloudWatch Logs + S3
  • Network Security: WAF + Shield + Network Firewall + Security Groups
  • IAM: IAM Identity Center + Cognito + STS + Organizations
  • Data Protection: KMS + Secrets Manager + S3 encryption + RDS encryption
  • Governance: Organizations + Control Tower + Config + Service Catalog

Automation Workflows:

  1. Automated Incident Response:
    • GuardDuty → EventBridge → Lambda → Isolate + Notify + Investigate
  2. Automated Compliance:
    • Config → Non-compliance → EventBridge → Systems Manager → Remediate
  3. Data Protection:
    • Macie → Sensitive data found → EventBridge → Lambda → Encrypt + Notify
  4. Multi-Account Security:
    • Organizations + Control Tower + Security Hub + Config Aggregator → Centralized visibility

Cross-Domain Decision Framework:

  1. Identify the requirement (threat detection, compliance, data protection, etc.)
  2. Select primary service (GuardDuty, Config, Macie, etc.)
  3. Add supporting services (CloudTrail for logs, KMS for encryption, etc.)
  4. Implement automation (EventBridge + Lambda for response)
  5. Centralize visibility (Security Hub for aggregation)
  6. Monitor and improve (CloudWatch for metrics, Trusted Advisor for recommendations)

Next Steps

Before taking the exam:

  1. Review all domain Quick Reference Cards (Domains 1-6)
  2. Complete all three Full Practice Tests and score 75%+ on each
  3. Review Study Strategies (Chapter 9) for test-taking techniques
  4. Complete the Final Checklist (Chapter 10) in your last week

Final Preparation:

  • Focus on weak areas identified in practice tests
  • Review common integration patterns and automation workflows

Chapter Summary

What We Covered

This chapter covered cross-domain integration scenarios that combine concepts from all six domains:

Scenario 1: Complete Security Architecture

  • Integrated all six domains into a comprehensive security architecture
  • Showed how threat detection, logging, infrastructure security, IAM, data protection, and governance work together
  • Demonstrated defense in depth with multiple layers of security controls

Scenario 2: Incident Response Workflow

  • Combined threat detection (GuardDuty) with automated response (EventBridge, Lambda)
  • Integrated logging (CloudTrail) with investigation (Detective)
  • Applied IAM policies for incident response team access
  • Used forensic isolation and evidence preservation techniques

Scenario 3: Multi-Account Security Operations

  • Centralized security management using Organizations and Control Tower
  • Aggregated findings from Security Hub across all accounts
  • Implemented cross-account logging and monitoring
  • Applied SCPs to enforce security policies organization-wide

Scenario 4: Data Protection Strategy

  • Combined encryption at rest (KMS) with encryption in transit (TLS)
  • Integrated access controls (IAM, bucket policies) with encryption
  • Implemented data lifecycle management with compliance requirements
  • Used Secrets Manager for credential management

Scenario 5: Compliance Automation

  • Automated compliance checks using Config rules and conformance packs
  • Collected evidence using Audit Manager
  • Remediated noncompliant resources automatically
  • Generated compliance reports for auditors

Scenario 6: Zero Trust Architecture

  • Implemented least privilege access with IAM and SCPs
  • Used VPC endpoints and PrivateLink to eliminate internet exposure
  • Applied network segmentation with security groups and NACLs
  • Enforced MFA and session policies for all access

Scenario 7: Hybrid Cloud Security

  • Secured connectivity between on-premises and AWS (VPN, Direct Connect)
  • Extended identity management to hybrid environments (IAM Identity Center)
  • Centralized logging from both on-premises and cloud resources
  • Applied consistent security policies across hybrid infrastructure

Scenario 8: DevSecOps Pipeline

  • Integrated security into CI/CD pipeline
  • Automated vulnerability scanning (Inspector, ECR)
  • Implemented IaC security scanning (CloudFormation, Terraform)
  • Used Secrets Manager for secure credential injection

Critical Takeaways

  1. Security is layered: No single service provides complete security. Combine multiple services for defense in depth.

  2. Automation is essential: Manual security processes don't scale. Automate detection, response, and remediation.

  3. Centralization simplifies management: Aggregate logs, findings, and policies in a central security account.

  4. Least privilege is the foundation: Start with no permissions and add only what's needed. Use IAM, SCPs, and permissions boundaries.

  5. Encryption everywhere: Encrypt data at rest and in transit. Use KMS for key management and audit trails.

  6. Compliance is continuous: Use Config rules and Audit Manager to continuously monitor compliance, not just during audits.

  7. Zero trust assumes breach: Don't trust anything by default. Verify every request, even from inside the network.

  8. Hybrid requires consistency: Apply the same security policies to on-premises and cloud resources.

  9. DevSecOps shifts security left: Integrate security early in the development process, not just at deployment.

  10. Incident response must be practiced: Test your incident response playbooks regularly. Automate as much as possible.

Self-Assessment Checklist

Test yourself on cross-domain scenarios. You should be able to:

Complete Security Architecture:

  • Design a multi-layer security architecture that integrates all six domains
  • Explain how GuardDuty findings trigger automated remediation workflows
  • Describe the flow of logs from services to centralized analysis
  • Design IAM policies that enforce least privilege across the architecture

Incident Response:

  • Design an automated incident response workflow from detection to remediation
  • Explain how to investigate an incident using Detective and CloudTrail
  • Describe the process for isolating compromised resources while preserving evidence
  • Create an incident response playbook using Systems Manager Automation

Multi-Account Security:

  • Design a multi-account security architecture using Organizations and Control Tower
  • Configure Security Hub to aggregate findings from all accounts
  • Implement cross-account logging to a central security account
  • Apply SCPs to enforce security policies across the organization

Data Protection:

  • Design a comprehensive data protection strategy with encryption and access controls
  • Implement data lifecycle management with compliance requirements
  • Configure Secrets Manager for automatic credential rotation
  • Apply KMS key policies for cross-account access

Compliance Automation:

  • Design an automated compliance monitoring system using Config and Audit Manager
  • Create Config rules to detect noncompliant resources
  • Implement automated remediation for common compliance violations
  • Generate compliance reports for auditors

Zero Trust Architecture:

  • Design a zero trust architecture with least privilege and network segmentation
  • Implement VPC endpoints to eliminate internet exposure
  • Configure MFA and session policies for all access
  • Apply network segmentation with security groups and NACLs

Hybrid Cloud Security:

  • Design secure connectivity between on-premises and AWS
  • Extend identity management to hybrid environments
  • Centralize logging from both on-premises and cloud resources
  • Apply consistent security policies across hybrid infrastructure

DevSecOps Pipeline:

  • Integrate security scanning into CI/CD pipeline
  • Automate vulnerability scanning for containers and EC2 instances
  • Implement IaC security scanning for CloudFormation templates
  • Use Secrets Manager for secure credential injection in pipelines

Practice Questions

Try these from your practice test bundles:

  • Full Practice Test 1: All 50 questions (tests cross-domain knowledge)
  • Full Practice Test 2: All 50 questions (different scenarios)
  • Full Practice Test 3: All 50 questions (advanced scenarios)
  • Service-Focused Bundles: Test your knowledge of how services integrate

Expected score: 75%+ to be exam-ready

If you scored below 75%:

  • Review the domain chapters for services you struggled with
  • Focus on understanding how services integrate (e.g., GuardDuty → EventBridge → Lambda)
  • Practice designing complete architectures, not just individual components
  • Revisit the cross-domain scenario diagrams

Quick Reference Card

Copy this to your notes for quick review:

Common Integration Patterns:

  • Detection → Response: GuardDuty → EventBridge → Lambda → Remediation
  • Logging → Analysis: CloudTrail → S3 → Athena → Insights
  • Compliance → Remediation: Config → Noncompliant → Lambda → Fix
  • Incident → Investigation: GuardDuty → Detective → Root Cause
  • Multi-Account → Centralized: Organizations → Delegated Admin → Security Hub Aggregation

Key Architectural Principles:

  • Defense in Depth: Multiple layers of security controls
  • Least Privilege: Minimum permissions needed for the task
  • Separation of Duties: No single person has complete control
  • Automation: Automate detection, response, and remediation
  • Centralization: Aggregate logs, findings, and policies
  • Encryption Everywhere: Encrypt data at rest and in transit
  • Zero Trust: Verify every request, assume breach
  • Continuous Compliance: Monitor compliance continuously, not just during audits

Decision Points for Integration:

  • Need automated response → GuardDuty + EventBridge + Lambda
  • Need centralized security → Organizations + Security Hub + delegated admin
  • Need compliance automation → Config + conformance packs + remediation
  • Need incident investigation → Detective + CloudTrail + VPC Flow Logs
  • Need data protection → KMS + encryption at rest/transit + access controls
  • Need hybrid security → VPN/Direct Connect + IAM Identity Center + centralized logging
  • Need DevSecOps → Inspector + ECR scanning + IaC scanning + Secrets Manager

You're now ready for Chapter 8: Study Strategies!

The next chapter will teach you effective study techniques and test-taking strategies for the exam.


Study Strategies & Test-Taking Techniques

Effective Study Techniques

The 3-Pass Method

Pass 1: Understanding (Weeks 1-6)

  • Read each chapter thoroughly from beginning to end
  • Take detailed notes on ⭐ Must Know items
  • Complete all practice exercises after each section
  • Create flashcards for key concepts and service features
  • Draw your own diagrams to reinforce understanding
  • Focus on understanding WHY, not just WHAT

Pass 2: Application (Weeks 7-8)

  • Review chapter summaries only (skip detailed content)
  • Focus on decision frameworks and comparison tables
  • Practice full-length tests (50 questions, 170 minutes)
  • Review incorrect answers and understand why you got them wrong
  • Identify weak areas and revisit those chapters
  • Practice explaining concepts out loud

Pass 3: Reinforcement (Weeks 9-10)

  • Review only flagged items and weak areas
  • Memorize critical facts (service limits, encryption algorithms)
  • Take final practice tests aiming for 80%+ scores
  • Review cheat sheet daily
  • Focus on exam-taking strategies
  • Build confidence through repetition

Active Learning Techniques

1. Teach Someone
Explain concepts out loud as if teaching someone else. This forces you to organize your thoughts and identify gaps in understanding. If you can't explain it simply, you don't understand it well enough.

Example: Explain to a friend (or rubber duck) how envelope encryption works, including why AWS uses it instead of encrypting data directly with KMS keys.

2. Draw Diagrams
Visualize architectures and data flows. Drawing forces you to think through how components interact. Use the diagrams in this guide as templates, then create your own variations.

Example: Draw a complete incident response architecture showing GuardDuty → EventBridge → Lambda → Systems Manager → EC2 isolation.

3. Write Scenarios
Create your own exam-style questions based on real-world scenarios. This helps you think like the exam writers and understand what they're testing.

Example: "A company needs to encrypt S3 data with audit trails of all decryption operations. What solution provides this?" (Answer: SSE-KMS with CloudTrail logging)

4. Compare Options
Create comparison tables for similar services or features. Understanding differences helps you choose the right option on the exam.

Example:

Feature SSE-S3 SSE-KMS SSE-C
Key Management AWS Customer (via KMS) Customer (outside AWS)
Audit Trail No Yes (CloudTrail) No
Cost Free $0.03/10K requests Free
Use Case Simple encryption Compliance, audit Full key control

Memory Aids

Mnemonics for Service Categories:

  • GSMID - GuardDuty, Security Hub, Macie, Inspector, Detective (Threat Detection Services)
  • CRAVE - CloudTrail, Route 53 logs, Athena, VPC Flow Logs, EventBridge (Logging & Analysis)
  • WANDS - WAF, ALB, NACLs, Detective, Security Groups (Network Security)
  • KISS - KMS, IAM, Secrets Manager, STS (Identity & Encryption)

Visual Patterns:

  • Preventive vs Detective: Preventive = SCPs, IAM policies (stop before it happens). Detective = Config, GuardDuty (alert after it happens)
  • Encryption Layers: Data in transit = TLS/VPN. Data at rest = KMS/EBS encryption. Data in use = CloudHSM
  • Access Control Layers: Edge = WAF. Network = Security Groups. Application = IAM. Data = KMS key policies

Number Patterns:

  • 1.25 Gbps: VPN tunnel throughput
  • 5,500 req/sec: KMS API rate limit
  • 7 years: Default Config history retention
  • 30 seconds: Dead Peer Detection timeout for VPN
  • 65,536 bytes: Maximum secret size in Secrets Manager

Test-Taking Strategies

Time Management

Total time: 170 minutes (2 hours 50 minutes)
Total questions: 65 (50 scored + 15 unscored)
Time per question: ~2.6 minutes average

Strategy:

  • First pass (90 minutes): Answer all questions you're confident about. Flag uncertain questions for review.
  • Second pass (50 minutes): Tackle flagged questions. Use elimination strategy.
  • Final pass (30 minutes): Review all answers, especially flagged ones. Check for careless mistakes.

Time Allocation Tips:

  • Spend no more than 3 minutes on any single question initially
  • Easy questions (1-2 minutes): Straightforward service selection or concept identification
  • Medium questions (2-3 minutes): Scenario-based with multiple valid options
  • Hard questions (3-4 minutes): Complex scenarios requiring integration of multiple concepts
  • If stuck after 3 minutes, flag and move on - come back later with fresh perspective

Question Analysis Method

Step 1: Read the scenario carefully (30 seconds)

  • Identify the company's situation and requirements
  • Note key constraints (cost, time, operational overhead)
  • Highlight security requirements (encryption, compliance, audit)
  • Look for qualifier words (MOST, LEAST, BEST, FIRST)

Step 2: Identify constraints (15 seconds)

  • Cost requirements: "cost-effective", "minimize cost"
  • Performance needs: "low latency", "high throughput"
  • Compliance requirements: "HIPAA", "PCI-DSS", "audit trail"
  • Operational overhead: "least operational overhead", "automated"
  • Security level: "most secure", "defense-in-depth"

Step 3: Eliminate wrong answers (30 seconds)

  • Remove options that violate stated constraints
  • Eliminate technically incorrect options (services that don't have claimed features)
  • Remove options that don't address the core problem
  • Look for "always" or "never" statements (usually wrong)

Step 4: Choose best answer (45 seconds)

  • Compare remaining options against requirements
  • Select option that best meets ALL requirements
  • Prefer AWS-managed services over self-managed
  • Prefer automated solutions over manual
  • Prefer defense-in-depth over single-layer security

Total time per question: ~2 minutes

Handling Difficult Questions

When stuck:

  1. Eliminate obviously wrong answers - Narrow down to 2-3 options
  2. Look for constraint keywords - "most secure" usually means multiple layers
  3. Choose most commonly recommended solution - AWS best practices
  4. Flag and move on - Don't spend more than 3 minutes initially
  5. Return with fresh perspective - Often the answer becomes clear later

Common traps to avoid:

  • ❌ Choosing the most complex solution (exam prefers simple, managed services)
  • ❌ Overthinking the question (usually straightforward if you know the concepts)
  • ❌ Ignoring qualifier words (MOST, LEAST, FIRST change the correct answer)
  • ❌ Selecting based on partial match (answer must address ALL requirements)

Keyword Recognition

Security Keywords:

  • "Audit trail" → CloudTrail, SSE-KMS (not SSE-S3)
  • "Immutable" → S3 Object Lock Compliance mode
  • "Prevent" → SCPs, IAM deny policies, WAF
  • "Detect" → GuardDuty, Config, Security Hub
  • "Encrypt in transit" → TLS, VPN, HTTPS
  • "Encrypt at rest" → KMS, EBS encryption, SSE-KMS

Operational Keywords:

  • "Least operational overhead" → Managed services, automation
  • "Cost-effective" → Native AWS services, serverless
  • "Scalable" → Auto Scaling, serverless, managed services
  • "Automated" → Lambda, EventBridge, Systems Manager

Compliance Keywords:

  • "Compliance" → Config, Security Hub, Audit Manager
  • "Regulatory" → Object Lock, CloudTrail, encryption
  • "Evidence" → Audit Manager, CloudTrail, Config history

Practice Test Strategy

How to Use Practice Tests

Diagnostic Test (Week 1):

  • Take one full practice test before studying
  • Don't worry about score - this establishes baseline
  • Identify weak domains for focused study
  • Review all answers (correct and incorrect) to understand patterns

Progress Tests (Weeks 4, 6, 8):

  • Take practice tests to measure progress
  • Aim for 10-15% improvement each time
  • Focus on weak areas between tests
  • Track which question types you miss most

Final Tests (Weeks 9-10):

  • Take 3-4 full practice tests
  • Simulate exam conditions (170 minutes, no breaks)
  • Aim for 80%+ scores consistently
  • Review only incorrect answers (don't waste time on correct ones)

Analyzing Practice Test Results

After each practice test:

  1. Calculate domain scores: How did you perform in each domain?
  2. Identify patterns: Are you missing "most secure" questions? Cost-effective questions?
  3. Review incorrect answers: Understand WHY you got it wrong
  4. Review correct answers you guessed: Ensure you understand the concept
  5. Update study plan: Focus on weak domains and question types

Score Interpretation:

  • Below 60%: Need significant study in this domain
  • 60-70%: Understand basics, need more practice
  • 70-80%: Good understanding, minor gaps to fill
  • Above 80%: Strong understanding, ready for exam

Common Mistakes to Avoid

During Practice:

  • ❌ Looking up answers while taking the test (defeats the purpose)
  • ❌ Not timing yourself (time management is critical)
  • ❌ Only reviewing incorrect answers (understand why correct answers are right)
  • ❌ Taking tests back-to-back without review (learn from mistakes first)

During Study:

  • ❌ Passive reading without active engagement
  • ❌ Skipping hands-on practice (use AWS Free Tier)
  • ❌ Memorizing without understanding
  • ❌ Ignoring weak areas (focus on what you don't know)

Exam Day Preparation

Week Before Exam

7 days before:

  • Take final practice test
  • Review all flagged topics
  • Create summary sheet of must-know facts

3 days before:

  • Light review only (cheat sheet, summaries)
  • No new topics
  • Focus on confidence building

1 day before:

  • Review cheat sheet (30 minutes)
  • Skim chapter summaries (1 hour)
  • Relax and get good sleep

Exam day morning:

  • Light breakfast
  • Review cheat sheet (15 minutes)
  • Arrive 30 minutes early

Mental Preparation

Confidence Building:

  • You've studied thoroughly - trust your preparation
  • Practice tests show you're ready
  • Exam is passable - 750/1000 is only 75%
  • You don't need to know everything perfectly

Stress Management:

  • Deep breathing if anxious
  • Skip difficult questions and return later
  • Remember: 15 questions are unscored (don't panic if some seem impossible)
  • Focus on one question at a time

Brain Dump Strategy

When exam starts, immediately write down (on provided materials):

  • Service limits: VPN 1.25 Gbps, KMS 5,500 req/sec
  • Encryption algorithms: AES-256, SHA-256, RSA-2048
  • Retention periods: Config 7 years, CloudTrail 90 days default
  • Port numbers: HTTPS 443, SSH 22, RDP 3389
  • Mnemonics: GSMID, CRAVE, WANDS, KISS

This frees your mind to focus on questions rather than trying to remember facts.

During Exam

Best Practices:

  • ✅ Read each question completely before looking at answers
  • ✅ Identify the qualifier word (MOST, LEAST, BEST, FIRST)
  • ✅ Eliminate obviously wrong answers first
  • ✅ Flag questions you're unsure about
  • ✅ Use all available time (don't rush)
  • ✅ Review flagged questions in second pass
  • ✅ Change answers only if you're confident (first instinct often correct)

Red Flags:

  • ❌ Spending more than 4 minutes on one question
  • ❌ Changing answers without good reason
  • ❌ Panicking about difficult questions (some are unscored)
  • ❌ Leaving questions blank (no penalty for guessing)

Advanced Test-Taking Strategies

Time Management Mastery

Exam Format:

  • Total time: 170 minutes (2 hours 50 minutes)
  • Total questions: 65 (50 scored + 15 unscored)
  • Time per question: ~2.6 minutes average
  • Passing score: 750/1000 (75%)

Three-Pass Strategy:

Pass 1 - Quick Wins (90 minutes):

  • Answer all questions you're confident about (1-2 minutes each)
  • Flag difficult questions for later
  • Don't get stuck - keep moving
  • Goal: Answer 45-50 questions

Pass 2 - Tackle Flagged (50 minutes):

  • Return to flagged questions
  • Spend 3-4 minutes per question
  • Use elimination strategy
  • Make educated guesses
  • Goal: Answer remaining 15-20 questions

Pass 3 - Final Review (30 minutes):

  • Review all flagged questions
  • Check for misread questions
  • Verify all questions answered
  • Trust your first instinct

Question Analysis Framework

Step 1: Identify the Scenario (30 seconds)

  • What type of company/situation?
  • What are they trying to accomplish?
  • What constraints exist?

Step 2: Extract Requirements (30 seconds)

  • Security requirements
  • Cost constraints
  • Operational overhead limits
  • Compliance needs
  • Performance requirements

Step 3: Note the Qualifier (10 seconds)

  • MOST secure
  • LEAST cost
  • LEAST operational overhead
  • BEST practice
  • FIRST step

Step 4: Eliminate Wrong Answers (30 seconds)

  • Remove options that don't meet requirements
  • Eliminate technically incorrect options
  • Remove options that violate constraints

Step 5: Choose Best Answer (20 seconds)

  • Select option that best meets ALL requirements
  • Consider the qualifier
  • Trust your knowledge

Handling Different Question Patterns

Pattern 1: "What is the MOST secure solution?"

What they're testing: Understanding of defense in depth and security best practices

How to answer:

  1. Look for multiple layers of security
  2. Prefer customer-managed keys over AWS-managed
  3. Prefer private connectivity over public
  4. Prefer automated enforcement over manual
  5. Look for encryption + access control + monitoring

Example:
"What is the MOST secure way to store database credentials?"

  • ❌ Environment variables (visible in console)
  • ❌ Parameter Store (less features than Secrets Manager)
  • ✅ Secrets Manager with automatic rotation + KMS encryption
  • ❌ Hardcoded in application (never secure)

Pattern 2: "What provides the LEAST operational overhead?"

What they're testing: Understanding of managed services and automation

How to answer:

  1. Prefer AWS-managed services over self-managed
  2. Prefer automated solutions over manual
  3. Prefer native integrations over custom code
  4. Avoid solutions requiring ongoing maintenance

Example:
"What provides vulnerability scanning with LEAST operational overhead?"

  • ❌ Deploy open-source scanner on EC2 (requires management)
  • ✅ Enable Amazon Inspector (fully managed, automatic)
  • ❌ Third-party SaaS scanner (requires integration)
  • ❌ Manual scanning with scripts (requires maintenance)

Pattern 3: "What is the MOST cost-effective solution?"

What they're testing: Understanding of service pricing and cost optimization

How to answer:

  1. Meet security requirements with lowest cost option
  2. Consider free tier services
  3. Avoid over-engineering
  4. Balance cost with security (don't sacrifice security for cost)

Example:
"What is the MOST cost-effective way to store non-rotating secrets?"

  • ✅ Systems Manager Parameter Store (free for standard parameters)
  • ❌ Secrets Manager ($0.40/secret/month)
  • ❌ S3 with encryption (storage costs + complexity)
  • ❌ DynamoDB (overkill for simple secrets)

Pattern 4: "A service is not working. What could be the cause?"

What they're testing: Troubleshooting skills and understanding of common misconfigurations

How to answer:

  1. Identify what's not working
  2. Recall common causes for that service
  3. Check permissions first (most common issue)
  4. Check configuration second
  5. Check network connectivity third

Example:
"CloudTrail is enabled but logs are not appearing in S3. What is the cause?"

  • ✅ S3 bucket policy doesn't allow CloudTrail to write
  • ❌ CloudTrail not enabled (question states it is)
  • ❌ Wrong region (logs would still appear)
  • ❌ KMS key issue (would show error, not missing logs)

Common Traps and How to Avoid Them

Trap 1: Partially Correct Answers

  • Option meets some requirements but not all
  • Always verify option meets ALL stated requirements

Example:
"Need to encrypt data in transit AND at rest"

  • ❌ Enable S3 encryption (only at rest)
  • ❌ Require HTTPS (only in transit)
  • ✅ S3 encryption + bucket policy requiring HTTPS

Trap 2: Overcomplicating Solutions

  • Custom solution when AWS service exists
  • Exam prefers simple, managed solutions

Example:

  • ❌ "Deploy Elasticsearch on EC2 for log analysis"
  • ✅ "Use CloudWatch Logs Insights for log analysis"

Trap 3: Ignoring the Qualifier

  • "MOST secure" ≠ "LEAST cost"
  • Read qualifier carefully

Trap 4: Confusing Similar Services

  • GuardDuty (threat detection) vs Detective (investigation)
  • Security Hub (aggregation) vs Config (compliance)
  • Secrets Manager (rotation) vs Parameter Store (simple storage)

Trap 5: "Always" or "Never" Statements

  • Absolute statements are usually wrong
  • Security is context-dependent

Keyword Recognition Guide

Security Keywords → Look For:

  • "Encrypt" → KMS, TLS, encryption at rest/transit
  • "Audit" → CloudTrail, Config, logging
  • "Detect" → GuardDuty, Security Hub, Detective
  • "Prevent" → SCPs, IAM policies, WAF
  • "Isolate" → Security groups, NACLs, network segmentation
  • "Rotate" → Secrets Manager, KMS key rotation
  • "Compliance" → Config, Security Hub, Audit Manager
  • "Sensitive data" → Macie
  • "Vulnerability" → Inspector
  • "DDoS" → Shield, WAF
  • "Web application" → WAF, CloudFront

Qualifier Keywords → Strategy:

  • "MOST secure" → Multiple layers, customer-managed, private, automated
  • "LEAST cost" → Cheapest option meeting requirements
  • "LEAST operational overhead" → Most automated, managed
  • "BEST practice" → AWS-recommended approach
  • "MOST scalable" → Serverless, auto-scaling
  • "FIRST step" → Initial action in sequence

Constraint Keywords → Implications:

  • "Must remain in region" → Data residency, SCPs
  • "Audit trail required" → CloudTrail, logging
  • "Automatic" → Managed services, automation
  • "Real-time" → Streaming, EventBridge
  • "Existing infrastructure" → Must integrate with current setup
  • "No code changes" → Service-level solution
  • "Centralized" → Multi-account, aggregation

Practice Test Strategy

Before Taking Practice Tests

Preparation:

  • Complete all study chapters first
  • Review cheat sheet
  • Set aside uninterrupted 170 minutes
  • Simulate exam environment (quiet, no distractions)

Mindset:

  • Treat it like the real exam
  • Don't look up answers during test
  • Use time management strategy
  • Flag difficult questions

During Practice Tests

Best Practices:

  • Start timer (170 minutes)
  • Read each question carefully
  • Use elimination strategy
  • Flag difficult questions
  • Keep moving forward
  • Check time every 15-20 questions

What to Track:

  • Time spent per question
  • Questions flagged
  • Confidence level per question
  • Domain of each question

After Practice Tests

Immediate Review:

  • Review ALL questions (not just incorrect)
  • Understand WHY correct answer is correct
  • Understand WHY incorrect answers are wrong
  • Note patterns in mistakes

Analysis:

  • Calculate score by domain
  • Identify weak domains (< 70%)
  • Identify weak services
  • Create remediation plan

Remediation:

  • Review study guide chapters for weak domains
  • Take domain-focused bundles for weak areas
  • Create flashcards for concepts you got wrong
  • Retake practice test after remediation

Score Interpretation:

  • < 60%: Need significant more study
  • 60-70%: On track, focus on weak areas
  • 70-80%: Good progress, refine understanding
  • 80%+: Ready for exam

Progressive Practice Schedule:

  1. Week 7: Beginner bundle (build confidence)
  2. Week 8: Intermediate bundle (test understanding)
  3. Week 9: Advanced bundle + Full Practice Test 1
  4. Week 10: Domain bundles for weak areas + Full Practice Test 2
  5. 1 week before exam: Full Practice Test 3 (should score 75%+)

Exam Day Preparation

Final Week Countdown

7 Days Before:

  • ✅ Take final full practice test
  • ✅ Score should be 75%+ consistently
  • ✅ Identify any remaining weak areas
  • ✅ Create final review list
  • ✅ Review cheat sheet

5 Days Before:

  • ✅ Review cheat sheet daily (30 minutes)
  • ✅ Focus on weak areas only
  • ✅ No new material
  • ✅ Light practice questions (20-30 per day)
  • ✅ Review comparison tables

3 Days Before:

  • ✅ Review chapter summaries
  • ✅ Review all ⭐ Must Know items
  • ✅ Practice explaining concepts out loud
  • ✅ Review service comparison tables
  • ✅ Get good sleep

2 Days Before:

  • ✅ Light review only (cheat sheet, summaries)
  • ✅ No intensive studying
  • ✅ Relax and rest
  • ✅ Prepare exam day materials
  • ✅ Confirm exam time and location

1 Day Before:

  • ✅ Review cheat sheet (30 minutes maximum)
  • ✅ No studying after lunch
  • ✅ Relax and get 8 hours sleep
  • ✅ Prepare what you'll bring
  • ✅ Set multiple alarms

Exam Day Morning:

  • ✅ Light breakfast (avoid heavy meal)
  • ✅ Review cheat sheet (15 minutes only)
  • ✅ Arrive 30 minutes early
  • ✅ Bring required ID
  • ✅ Bring confirmation email/code

What to Bring

Required:

  • Government-issued photo ID
  • Exam confirmation email/code
  • Arrive 30 minutes early

Recommended:

  • Water bottle (if allowed)
  • Jacket (testing centers can be cold)
  • Positive attitude

Not Allowed:

  • Study materials
  • Electronic devices
  • Notes or paper
  • Food (usually)

Mental Preparation

Confidence Building:

  • "I've studied thoroughly for 6-10 weeks"
  • "I've scored 75%+ on practice tests"
  • "I understand the concepts deeply"
  • "I can eliminate wrong answers effectively"
  • "I'm ready for this exam"

Stress Management Techniques:

  • Deep Breathing: 4 counts in, 4 hold, 4 out, 4 hold (repeat 3 times)
  • Positive Visualization: Imagine yourself passing the exam
  • Muscle Relaxation: Tense and release muscle groups
  • Mindfulness: Focus on present moment, not worries

During Exam Anxiety:

  • Take deep breaths
  • Skip difficult question and return later
  • Remember: 15 questions are unscored
  • Focus on one question at a time
  • You have plenty of time

During the Exam

First 5 Minutes:

  • Read all instructions carefully
  • Note total questions (65) and time (170 minutes)
  • Take 3 deep breaths
  • Start with confidence

Throughout Exam:

  • Read each question twice
  • Underline key requirements
  • Note the qualifier (MOST, LEAST, BEST)
  • Use elimination strategy
  • Flag difficult questions
  • Keep moving forward
  • Check time every 15-20 questions

If You're Stuck:

  • Skip and flag the question
  • Don't spend more than 4 minutes
  • Move to next question
  • Return during second pass
  • Make educated guess if still unsure
  • Never leave blank (no penalty)

Final 15 Minutes:

  • Review all flagged questions
  • Verify all questions answered
  • Check for misread questions
  • Double-check qualifier words
  • Submit when confident

After the Exam

Immediate Results:

  • Pass/fail shown immediately
  • Detailed score report available later (5 business days)
  • Don't stress about individual questions
  • Celebrate your effort

If You Pass 🎉:

  • Congratulations! You're AWS Certified Security - Specialty
  • Certificate available in AWS Certification account within 5 days
  • Digital badge available immediately
  • Update LinkedIn, resume, email signature
  • Consider next certification (Solutions Architect Professional, DevOps Engineer)
  • Share your success with study group

If You Don't Pass:

  • Don't be discouraged - many people need 2-3 attempts
  • Review score report to identify weak domains
  • Focus study on weak areas (< 70%)
  • Retake domain-focused practice bundles
  • Schedule retake after 14-day waiting period
  • You can do this - learn from the experience

Common Study Mistakes to Avoid

Mistake 1: Passive Reading

What people do: Read study guide without taking notes or practicing
What to do instead: Take notes, draw diagrams, practice questions, teach others

Mistake 2: Cramming

What people do: Study intensively the week before exam
What to do instead: Study consistently over 6-10 weeks with spaced repetition

Mistake 3: Memorizing Without Understanding

What people do: Memorize answers without understanding why
What to do instead: Understand concepts deeply, know WHY answers are correct

Mistake 4: Skipping Practice Tests

What people do: Go into exam without taking practice tests
What to do instead: Take at least 3 full practice tests, review all questions

Mistake 5: Ignoring Weak Areas

What people do: Focus only on comfortable topics
What to do instead: Spend extra time on weak domains (< 70% on practice tests)

Mistake 6: Not Using Hands-On Practice

What people do: Only read about services
What to do instead: Practice in AWS console with free-tier account

Mistake 7: Studying Alone

What people do: Study in isolation without discussion
What to do instead: Join study groups, explain concepts to others

Mistake 8: Rushing Through Practice Tests

What people do: Take practice tests quickly without simulating exam conditions
What to do instead: Simulate real exam (170 minutes, quiet environment, no interruptions)


Success Stories and Tips

From Recent Test-Takers

Sarah, Cloud Security Engineer:
"I created flashcards for every AWS security service and reviewed them during my commute. By exam day, I could instantly recall what each service does and when to use it. The key was consistent daily review, not cramming."

Michael, Solutions Architect:
"I set up a free-tier AWS account and practiced everything hands-on. Seeing how GuardDuty findings look, how to create Config rules, and how to set up VPC Flow Logs made the concepts click. Hands-on practice was invaluable."

Jennifer, Security Consultant:
"I joined an AWS study group on LinkedIn and we met weekly to discuss concepts. Teaching others helped me identify gaps in my understanding. If I couldn't explain it simply, I didn't understand it well enough."

David, DevOps Engineer:
"I took practice tests every weekend and tracked my scores in a spreadsheet. Seeing my progress from 55% to 85% over 8 weeks motivated me to keep studying. The practice tests showed me exactly what I needed to focus on."

Lisa, Security Analyst:
"I focused on understanding WHY answers were correct, not just memorizing. This helped me handle questions I hadn't seen before. The exam tests understanding, not memorization."

Key Takeaways from Successful Test-Takers

  1. Consistency beats intensity: Study 2 hours daily for 10 weeks beats 20 hours/day for 1 week
  2. Hands-on practice is essential: Reading alone isn't enough
  3. Practice tests reveal gaps: Take multiple practice tests and review thoroughly
  4. Teach others: Explaining concepts solidifies understanding
  5. Focus on weak areas: Spend 70% of time on domains where you score < 70%
  6. Understand, don't memorize: Exam tests conceptual understanding
  7. Use multiple resources: Study guide + AWS docs + hands-on + practice tests
  8. Join a community: Study groups provide motivation and different perspectives

Chapter 9 Complete

Next Chapter: 10_final_checklist - Final Week Preparation Checklist


Chapter Summary

Key Study Strategies

  1. 3-Pass Method: Understanding → Application → Reinforcement
  2. Active Learning: Teach others, draw diagrams, create scenarios
  3. Spaced Repetition: Review material at increasing intervals
  4. Practice Tests: Take multiple tests, review thoroughly
  5. Hands-On: Set up free-tier account, practice configurations
  6. Focus on Weak Areas: Spend 70% of time on domains < 70%

Test-Taking Strategies

  1. Time Management: 2.6 minutes per question, flag and move on
  2. Question Analysis: Read scenario, identify constraints, eliminate wrong answers
  3. Keyword Recognition: "most secure", "least operational overhead", "most cost-effective"
  4. Avoid Traps: Don't choose single service when multiple needed
  5. Trust Preparation: Don't second-guess, trust your study

Final Preparation

  • Score 75%+ on all practice tests
  • Review all ⭐ Must Know items
  • Understand WHY answers are correct
  • Can design end-to-end solutions
  • Know when to use each service
  • Understand service integrations

Chapter 8 Complete

Next Chapter: 10_final_checklist - Final Week Preparation Checklist


Chapter Summary

What We Covered

This chapter provided effective study strategies and test-taking techniques:

Study Techniques: The 3-Pass Method for progressive learning, active learning techniques (teaching, drawing, writing, comparing), and memory aids (mnemonics, visual patterns, spaced repetition).

Test-Taking Strategies: Time management for the 170-minute exam, question analysis method (read scenario, identify constraints, eliminate wrong answers, choose best answer), and handling difficult questions.

Practice Approach: Using practice test bundles effectively, analyzing mistakes, identifying weak areas, and progressive difficulty (beginner → intermediate → advanced).

Final Preparation: Week-by-week study plan, final week checklist, exam day preparation, and mental readiness.

Critical Takeaways

  1. Active Learning Works: Passive reading is not enough. Teach concepts to others, draw diagrams, write scenarios, and compare options to truly understand the material.

  2. Practice Tests are Essential: Take full practice tests under exam conditions (170 minutes, 50 questions). Analyze every mistake to identify knowledge gaps and question patterns.

  3. Time Management is Critical: You have approximately 3.4 minutes per question. Use the first pass to answer easy questions, second pass for flagged questions, and final pass for review.

  4. Understand, Don't Memorize: The exam tests understanding, not memorization. Focus on WHY services work the way they do, not just WHAT they do.

  5. Eliminate First: Use the process of elimination to remove obviously wrong answers. This increases your odds even if you're not 100% certain of the correct answer.

  6. Keywords Matter: Learn to identify constraint keywords (cost-effective, minimal operational overhead, most secure, least privilege) that guide you to the correct answer.

  7. Mistakes are Learning: Every mistake on a practice test is a learning opportunity. Review the explanation, understand why you were wrong, and study that topic more deeply.

  8. Confidence Builds: Start with beginner practice tests to build confidence, progress to intermediate tests to develop skills, and finish with advanced tests to master edge cases.

Self-Assessment Checklist

Before taking the exam:

  • I've completed all domain chapters in this study guide
  • I've scored 75%+ on at least two full practice tests
  • I can explain key concepts without looking at notes
  • I recognize common question patterns and keywords
  • I can eliminate wrong answers quickly
  • I manage my time effectively during practice tests
  • I've reviewed all my mistakes from practice tests
  • I understand WHY answers are correct, not just WHAT they are
  • I'm comfortable with cross-domain scenarios
  • I've practiced with all difficulty levels (beginner, intermediate, advanced)

Final Reminders

Study Approach:

  • Study consistently (2-3 hours daily) rather than cramming
  • Take breaks every 45-60 minutes to maintain focus
  • Review weak areas multiple times with spaced repetition
  • Use multiple learning methods (reading, diagrams, practice, teaching)

Practice Tests:

  • Take practice tests under exam conditions (timed, no distractions)
  • Review every question, even ones you got correct
  • Track your scores by domain to identify weak areas
  • Retake practice tests after studying weak areas

Exam Day:

  • Get 8 hours of sleep the night before
  • Eat a good breakfast
  • Arrive 30 minutes early
  • Do a quick brain dump of key facts at the start
  • Trust your preparation and stay calm

Remember:

  • You don't need to score 100% to pass (750/1000 = 75%)
  • The exam uses compensatory scoring (strong domains can offset weak domains)
  • If you're consistently scoring 75%+ on practice tests, you're ready

Chapter Summary

What We Covered

This chapter covered effective study strategies and test-taking techniques for the AWS Certified Security - Specialty exam:

Study Techniques:

  • The 3-Pass Method for progressive learning
  • Active learning techniques (teaching, drawing, writing, comparing)
  • Memory aids and mnemonics for retention
  • Spaced repetition for long-term memory

Time Management:

  • Exam timing strategy (170 minutes for 65 questions)
  • Three-pass approach during the exam
  • Time allocation per question
  • When to flag and move on

Question Analysis:

  • Reading scenarios effectively
  • Identifying constraints and requirements
  • Eliminating wrong answers systematically
  • Choosing the best answer among multiple correct options

Test-Taking Strategies:

  • Handling difficult questions
  • Managing exam anxiety
  • Using the process of elimination
  • Recognizing question patterns

Common Pitfalls:

  • Overthinking questions
  • Missing key constraint words
  • Choosing "technically correct" instead of "best practice"
  • Running out of time

Critical Takeaways

  1. The exam tests practical knowledge: Focus on understanding concepts and applying them to real-world scenarios, not just memorizing facts.

  2. Read the scenario carefully: The first paragraph sets the context. The second paragraph asks the question. Don't skip the scenario.

  3. Identify constraints: Look for words like "most cost-effective," "least operational overhead," "most secure," "fastest to implement."

  4. Eliminate obviously wrong answers first: This increases your odds from 25% to 33% or 50%.

  5. Choose AWS best practices: When multiple answers are technically correct, choose the one that follows AWS best practices.

  6. Time management is critical: Don't spend more than 2-3 minutes on any single question initially. Flag and move on.

  7. Trust your preparation: Your first instinct is usually correct. Don't second-guess yourself unless you find a clear error.

  8. Practice with realistic questions: Use the practice test bundles to simulate exam conditions.

  9. Review your mistakes: Understand why you got questions wrong. This is more valuable than getting questions right.

  10. Stay calm and focused: Anxiety reduces performance. Take deep breaths, read carefully, and trust your knowledge.

Self-Assessment Checklist

Before taking the exam, ensure you can:

Study Preparation:

  • I've completed all six domain chapters
  • I've reviewed the integration chapter
  • I've taken at least 3 full practice tests
  • I'm scoring 75%+ on practice tests consistently
  • I've reviewed all my mistakes and understand why I got them wrong

Content Mastery:

  • I can explain the purpose and use cases for all major security services
  • I can design security architectures that integrate multiple services
  • I can troubleshoot common security issues
  • I can apply AWS security best practices
  • I can differentiate between similar services (e.g., GuardDuty vs Macie)

Test-Taking Skills:

  • I can read and analyze exam scenarios quickly
  • I can identify constraints and requirements
  • I can eliminate wrong answers systematically
  • I can manage my time effectively during practice tests
  • I stay calm and focused under pressure

Exam Readiness:

  • I've reviewed the cheat sheet
  • I've completed the final checklist
  • I've scheduled my exam
  • I know the exam format and rules
  • I'm confident in my preparation

Final Preparation Tips

One Week Before Exam:

  • Take a full practice test every other day
  • Review mistakes immediately after each test
  • Focus on weak areas identified in practice tests
  • Review the cheat sheet daily
  • Get adequate sleep (7-8 hours)

Day Before Exam:

  • Light review only (cheat sheet, quick reference cards)
  • Don't try to learn new topics
  • Prepare exam day materials (ID, confirmation)
  • Get a good night's sleep
  • Stay hydrated and eat well

Exam Day:

  • Arrive 30 minutes early
  • Do a brain dump of key facts on scratch paper
  • Read each question carefully
  • Manage your time (flag difficult questions)
  • Review flagged questions at the end
  • Stay calm and trust your preparation

Practice Test Strategy

How to Use Practice Tests:

  1. Simulate exam conditions: 170 minutes, no distractions, no notes
  2. Don't guess randomly: Try to eliminate wrong answers first
  3. Flag questions you're unsure about: Review them at the end
  4. Review immediately after: Understand why you got questions wrong
  5. Track your scores: Aim for consistent improvement

Practice Test Schedule:

  • Week 1-6: Study domain chapters, take domain-focused bundles
  • Week 7: Take difficulty-based bundles (beginner → intermediate → advanced)
  • Week 8: Take full practice tests (1 every other day)
  • Week 9: Review mistakes, retake weak domain bundles
  • Week 10: Final review, take last practice test, review cheat sheet

Score Interpretation:

  • Below 60%: Need more study time, review domain chapters
  • 60-70%: On track, focus on weak areas
  • 70-80%: Good progress, continue practicing
  • 80%+: Exam-ready, maintain knowledge with light review

You're now ready for Chapter 9: Final Checklist!

The next chapter provides a comprehensive checklist for your final week of preparation.


Final Week Checklist

7 Days Before Exam

Knowledge Audit

Go through this comprehensive checklist and mark items you're confident about:

Domain 1: Threat Detection and Incident Response (14%)

  • I can explain how GuardDuty detects threats using ML and threat intelligence
  • I understand the difference between GuardDuty finding types (Recon, InstanceCredentialExfiltration, etc.)
  • I know how to automate incident response using EventBridge and Lambda
  • I can describe the four-step incident response process (detect, investigate, respond, recover)
  • I understand how Detective builds behavior graphs for investigation
  • I know how to use Athena to query CloudTrail logs for threat hunting
  • I can explain how to isolate compromised EC2 instances
  • I understand credential rotation strategies for compromised credentials
  • I know how to capture forensic data (EBS snapshots, memory dumps)
  • I can describe how to protect forensic artifacts with S3 Object Lock

Domain 2: Security Logging and Monitoring (18%)

  • I understand what CloudTrail logs and what it doesn't log
  • I know the difference between management events and data events in CloudTrail
  • I can explain how to enable organization-wide CloudTrail
  • I understand VPC Flow Logs format and how to analyze them
  • I know how to create CloudWatch metric filters for security events
  • I can describe how to set up CloudWatch alarms for anomalies
  • I understand how to centralize logs across multiple accounts
  • I know how to implement log retention and lifecycle policies
  • I can explain how to troubleshoot missing logs
  • I understand how to use CloudWatch Logs Insights for log analysis

Domain 3: Infrastructure Security (20%)

  • I can explain the difference between security groups and NACLs
  • I understand when to use AWS WAF vs AWS Shield
  • I know how to configure WAF rules for OWASP Top 10 protection
  • I can describe how to implement network segmentation with VPCs
  • I understand how to use VPC endpoints for private connectivity
  • I know how to configure Transit Gateway for multi-VPC connectivity
  • I can explain how to use Network Firewall for deep packet inspection
  • I understand EC2 patching strategies with Systems Manager
  • I know how to scan for vulnerabilities with Inspector
  • I can describe how to harden EC2 instances and AMIs

Domain 4: Identity and Access Management (16%)

  • I understand the difference between IAM users, roles, and groups
  • I know how to implement federated access with SAML and OIDC
  • I can explain how IAM Identity Center works for multi-account access
  • I understand the difference between identity-based and resource-based policies
  • I know how to use IAM policy conditions (IP address, MFA, time-based)
  • I can describe the difference between RBAC and ABAC
  • I understand how to implement least privilege access
  • I know how to use IAM Access Analyzer to identify overly permissive policies
  • I can explain how to troubleshoot IAM permission issues
  • I understand how to use STS for temporary credentials

Domain 5: Data Protection (18%)

  • I can explain the difference between SSE-S3, SSE-KMS, and SSE-C
  • I understand how envelope encryption works
  • I know when to use customer-managed keys vs AWS-managed keys
  • I can describe how KMS key rotation works
  • I understand the difference between S3 Object Lock Compliance and Governance modes
  • I know how to implement MFA Delete for S3
  • I can explain how Secrets Manager rotation works
  • I understand the difference between Secrets Manager and Parameter Store
  • I know how to configure TLS/SSL with ACM
  • I can describe how to implement VPN for encrypted connectivity

Domain 6: Management and Security Governance (14%)

  • I understand how AWS Organizations works and the role of SCPs
  • I know the difference between SCPs and IAM policies
  • I can explain how Control Tower automates account provisioning
  • I understand the difference between mandatory, strongly recommended, and elective guardrails
  • I know how to use AWS Config for continuous compliance monitoring
  • I can describe how to create custom Config rules
  • I understand how to use Config aggregator for multi-account compliance
  • I know how to implement automatic remediation with Config
  • I can explain how to use Security Hub for compliance standards
  • I understand how to use Audit Manager for evidence collection

If you checked fewer than 80% in any domain: Review that domain's chapter thoroughly.

Practice Test Marathon

Day 7 (Today): Full Practice Test 1

  • Take 50-question test in 170 minutes
  • Simulate exam conditions (no breaks, no distractions)
  • Target score: 60%+ (baseline)
  • Review ALL answers (correct and incorrect)
  • Identify weak domains

Day 6: Review and Study

  • Focus on domains where you scored below 70%
  • Review chapter summaries for weak domains
  • Create flashcards for concepts you missed
  • No practice tests today - focus on learning

Day 5: Full Practice Test 2

  • Take another 50-question test
  • Target score: 70%+ (improvement)
  • Review only incorrect answers
  • Note question patterns you're missing

Day 4: Targeted Practice

  • Take domain-specific practice tests for weak areas
  • Review decision frameworks and comparison tables
  • Practice explaining concepts out loud
  • Create summary notes for difficult topics

Day 3: Full Practice Test 3

  • Take final full-length test
  • Target score: 75%+ (exam-ready)
  • Review flagged questions
  • Build confidence with strong performance

Day 2: Light Review

  • Review cheat sheet (1 hour)
  • Skim chapter summaries (1 hour)
  • Review your summary notes
  • No new topics - reinforce what you know

Day 1: Rest and Relax

  • Light review of cheat sheet only (30 minutes)
  • Get 8 hours of sleep
  • Prepare exam day materials
  • Visualize success

Day Before Exam

Final Review (2-3 hours max)

Hour 1: Cheat Sheet Review

  • Read through entire cheat sheet
  • Focus on ⭐ Must Know items
  • Review service comparison tables
  • Memorize critical numbers and limits

Hour 2: Chapter Summaries

  • Skim all chapter summaries
  • Review decision frameworks
  • Look at quick reference cards
  • Refresh memory on key concepts

Hour 3: Flagged Items

  • Review topics you flagged during study
  • Clarify any remaining confusion
  • Practice difficult concepts one last time
  • Build confidence with what you know

Don't: Try to learn new topics or cram complex concepts

Mental Preparation

Confidence Building:

  • Review your practice test scores - you're ready!
  • Remember: You only need 750/1000 (75%) to pass
  • You've studied thoroughly and practiced extensively
  • Trust your preparation and first instincts

Stress Management:

  • Exercise or take a walk (reduces anxiety)
  • Avoid caffeine after 2 PM (affects sleep)
  • Practice deep breathing exercises
  • Visualize yourself succeeding on the exam

Sleep Preparation:

  • Go to bed at regular time (not too early)
  • Avoid screens 1 hour before bed
  • Set multiple alarms for exam day
  • Lay out clothes and materials the night before

Exam Day Materials

Required:

  • Two forms of ID (government-issued photo ID + credit card)
  • Confirmation email with exam details
  • Directions to testing center (if in-person)
  • Computer setup tested (if online proctored)

Recommended:

  • Water bottle (if allowed at testing center)
  • Light snack for before exam
  • Jacket (testing centers can be cold)
  • Arrive 30 minutes early

Not Allowed:

  • ❌ Mobile phones or smart watches
  • ❌ Notes or study materials
  • ❌ Food or drinks (except water, if allowed)
  • ❌ Bags or backpacks

Exam Day

Morning Routine

3 hours before exam:

  • Wake up at regular time (not too early)
  • Eat a good breakfast (protein + complex carbs)
  • Avoid excessive caffeine (causes jitters)
  • Review cheat sheet for 15-30 minutes only

1 hour before exam:

  • Arrive at testing center (or log in for online)
  • Use restroom
  • Do light stretching or breathing exercises
  • Clear your mind and focus

At testing center:

  • Check in 30 minutes early
  • Store all personal items in locker
  • Review testing center rules
  • Take a few deep breaths before starting

Brain Dump Strategy

First 2 minutes of exam (before looking at questions):

Write down on provided materials:

Service Limits:

  • VPN: 1.25 Gbps per tunnel
  • KMS: 5,500 requests/second
  • Config: 150 rules per region
  • Organizations: 5 SCPs per account/OU

Encryption Standards:

  • Symmetric: AES-256-GCM
  • Asymmetric: RSA-2048, RSA-4096
  • Hashing: SHA-256, SHA-384
  • TLS: Version 1.2 minimum

Port Numbers:

  • HTTPS: 443
  • SSH: 22
  • RDP: 3389
  • MySQL: 3306
  • PostgreSQL: 5432

Mnemonics:

  • GSMID: GuardDuty, Security Hub, Macie, Inspector, Detective
  • CRAVE: CloudTrail, Route 53, Athena, VPC Flow Logs, EventBridge
  • WANDS: WAF, ALB, NACLs, Detective, Security Groups

Key Differences:

  • Preventive: SCPs, IAM policies, WAF
  • Detective: Config, GuardDuty, Security Hub
  • SSE-S3: AWS-managed, no audit trail
  • SSE-KMS: Customer-managed, CloudTrail audit
  • Compliance mode: Immutable, even root can't delete
  • Governance mode: Can be bypassed with permission

During Exam

Time Management:

  • 170 minutes for 65 questions = 2.6 minutes per question
  • First pass (90 min): Answer confident questions, flag uncertain
  • Second pass (50 min): Tackle flagged questions
  • Final pass (30 min): Review all answers

Question Strategy:

  1. Read scenario completely
  2. Identify qualifier word (MOST, LEAST, BEST)
  3. Note constraints (cost, security, operational overhead)
  4. Eliminate wrong answers
  5. Choose best remaining option
  6. Flag if uncertain, move on

Red Flags to Watch For:

  • "Always" or "Never" statements (usually wrong)
  • Options that don't address all requirements
  • Overly complex solutions (prefer simple, managed)
  • Options that violate stated constraints

If Stuck:

  • Eliminate obviously wrong answers
  • Choose most commonly recommended AWS solution
  • Flag and move on (don't spend more than 3 minutes)
  • Return with fresh perspective later

After Exam

Immediate:

  • You'll see "Pass" or "Fail" on screen
  • Detailed score report available in 5 business days
  • Certificate available in AWS Certification account

If you pass:

  • Congratulations! 🎉
  • Download certificate from AWS Certification account
  • Add to LinkedIn and resume
  • Consider next certification (AWS Solutions Architect Professional, etc.)

If you don't pass:

  • Don't be discouraged - many people need multiple attempts
  • Review score report to identify weak domains
  • Focus study on those domains
  • Wait 14 days before retaking
  • You can do this!

Final Reminders

What You Know

You've studied:

  • ✅ 6 domains of security knowledge
  • ✅ 50+ AWS security services
  • ✅ Hundreds of security concepts and best practices
  • ✅ Multiple practice tests with detailed explanations
  • ✅ Real-world scenarios and integration patterns

What to Remember

On exam day:

  • Trust your preparation
  • Read questions carefully
  • Manage your time
  • Don't overthink
  • Flag and move on if stuck
  • Review flagged questions
  • Use all available time

Key principles:

  • Prefer AWS-managed services
  • Choose automated solutions
  • Implement defense-in-depth
  • Follow least privilege
  • Enable logging and monitoring
  • Encrypt data at rest and in transit

You're Ready!

You've put in the work. You've studied the concepts. You've practiced the questions. You understand AWS security.

Now go pass that exam! 🚀

Good luck!



Final Words

You're Ready When...

  • You score 75%+ on all practice tests consistently
  • You can explain key concepts without notes
  • You recognize question patterns instantly
  • You make decisions quickly using frameworks
  • You understand service integrations
  • You can troubleshoot security issues
  • You know when to use each service
  • You understand trade-offs between approaches

Remember on Exam Day

Key Principles:

  • Prefer AWS-managed services
  • Choose automated solutions
  • Implement defense-in-depth
  • Follow least privilege
  • Enable logging and monitoring
  • Encrypt data at rest and in transit

Exam Strategy:

  • Trust your preparation
  • Read questions carefully
  • Manage your time well
  • Don't overthink
  • Flag and move on if stuck
  • Review flagged questions
  • Use all available time

You've Got This!

You've put in the work. You've studied the concepts. You've practiced the questions. You understand AWS security.

Now go pass that exam! 🚀

Good luck on your AWS Certified Security - Specialty certification!


Study Guide Complete

Total Chapters: 12 (Overview + 6 Domains + Integration + Strategies + Checklist + Appendices)

Final Thoughts

You're Ready When...

Check all of these before scheduling your exam:

  • Knowledge: You score 75%+ consistently on full practice tests
  • Understanding: You can explain concepts in your own words without notes
  • Application: You can design security architectures that integrate multiple services
  • Troubleshooting: You can diagnose and fix common security issues
  • Speed: You can complete practice tests within the time limit
  • Confidence: You feel prepared and ready to take the exam

Remember on Exam Day

Before the Exam:

  • Arrive 30 minutes early
  • Bring two forms of ID
  • Use the restroom before starting
  • Do a brain dump of key facts on scratch paper

During the Exam:

  • Read each question carefully (don't skim)
  • Identify constraints and requirements
  • Eliminate obviously wrong answers
  • Choose AWS best practices when multiple answers are correct
  • Flag difficult questions and move on
  • Manage your time (2-3 minutes per question)
  • Review flagged questions at the end

Stay Calm:

  • Take deep breaths if you feel anxious
  • Don't panic if you encounter difficult questions
  • Trust your preparation and knowledge
  • Remember that you don't need 100% to pass (750/1000 = 75%)

After the Exam

Pass or Fail:

  • You'll receive a preliminary pass/fail result immediately
  • Official score report arrives within 5 business days
  • Passing score is 750/1000 (75%)

If You Pass:

  • Congratulations! You're now AWS Certified Security - Specialty
  • Update your resume and LinkedIn profile
  • Download your digital badge from AWS Certification
  • Consider pursuing other AWS certifications

If You Don't Pass:

  • Don't be discouraged - many people need multiple attempts
  • Review your score report to identify weak areas
  • Focus on those areas and retake practice tests
  • Schedule a retake after 14 days (required waiting period)
  • You can retake the exam as many times as needed

Certification Maintenance

Recertification:

  • AWS Certified Security - Specialty is valid for 3 years
  • Recertify by retaking the exam or earning a higher-level certification
  • Start preparing 6 months before expiration

Continuing Education:

  • Stay updated with new AWS security services and features
  • Attend AWS re:Invent and security-focused sessions
  • Read AWS security blogs and whitepapers
  • Practice hands-on with new security services

Congratulations!

You've completed the comprehensive study guide for AWS Certified Security - Specialty (SCS-C02). You've learned:

  • Domain 1: Threat Detection and Incident Response (14%)
  • Domain 2: Security Logging and Monitoring (18%)
  • Domain 3: Infrastructure Security (20%)
  • Domain 4: Identity and Access Management (16%)
  • Domain 5: Data Protection (18%)
  • Domain 6: Management and Security Governance (14%)
  • Integration: How all domains work together in real-world scenarios
  • Study Strategies: Effective learning and test-taking techniques

Total Study Time: 6-10 weeks (2-3 hours daily)
Total Word Count: ~150,000 words
Total Diagrams: 123 Mermaid diagrams
Practice Questions: 500 questions across 29 practice test bundles

You're now equipped with the knowledge and skills to pass the AWS Certified Security - Specialty exam. Trust your preparation, stay calm, and do your best.

Good luck on your certification journey! 🎯


Next Steps:

  1. Review the cheat sheet one more time
  2. Take a final practice test
  3. Schedule your exam
  4. Get a good night's sleep
  5. Pass the exam!

You've got this! 💪


Appendices

Appendix A: Quick Reference Tables

Service Comparison Matrix

Threat Detection Services:

Service Purpose Detection Method Cost Model
GuardDuty Threat detection ML + threat intelligence Per GB analyzed
Security Hub Finding aggregation Collects from other services Per check per account
Macie Sensitive data discovery ML pattern matching Per GB scanned
Inspector Vulnerability scanning Agent-based assessment Per instance assessed
Detective Investigation Behavior graph analysis Per GB ingested

Logging Services:

Service What It Logs Retention Cost
CloudTrail API calls 90 days (event history) Per 100K events
VPC Flow Logs Network traffic Configurable Per GB ingested
CloudWatch Logs Application logs Configurable Per GB ingested
S3 Access Logs Object access Indefinite Storage cost only
Route 53 Query Logs DNS queries Configurable Per million queries

Encryption Services:

Service Use Case Key Management Audit Trail
SSE-S3 Simple S3 encryption AWS-managed No
SSE-KMS S3 with audit trail Customer-managed (KMS) Yes (CloudTrail)
SSE-C Customer-provided keys Customer (outside AWS) No
Client-side Encrypt before upload Customer No

Secret Management:

Feature Secrets Manager Parameter Store KMS
Purpose Secrets with rotation Configuration + secrets Encryption keys
Rotation Automatic (built-in) Manual Automatic (yearly)
Cost $0.40/secret/month Free (Standard), $0.05/parameter (Advanced) $1/key/month
Size Limit 64 KB 4 KB (Standard), 8 KB (Advanced) N/A (keys only)
Use Case Database credentials, API keys App config, simple secrets Encryption operations

Common Formulas and Calculations

VPN Throughput:

  • Single tunnel: 1.25 Gbps
  • With ECMP (4 tunnels): 5 Gbps
  • Accelerated VPN: Same throughput, lower latency

KMS Request Limits:

  • Shared quota: 5,500 requests/second
  • Per-operation quotas vary (Encrypt: 5,500, Decrypt: 5,500, GenerateDataKey: 5,500)
  • Request increase if needed for high-throughput workloads

CloudTrail Event Delivery:

  • Typical delivery: Within 15 minutes
  • Event history: 90 days (free)
  • Long-term storage: S3 bucket (configurable retention)

Config Evaluation:

  • Change-triggered: Evaluated when resource changes
  • Periodic: Every 1, 3, 6, 12, or 24 hours
  • Maximum rules: 150 per region (can request increase)

Limits & Constraints

Organizations:

  • Maximum accounts: 1,000 (can request increase)
  • Maximum OUs: 1,000
  • Maximum OU nesting: 5 levels
  • Maximum SCPs per account/OU: 5
  • SCP size: 5,120 characters

IAM:

  • Users per account: 5,000
  • Groups per account: 300
  • Roles per account: 1,000
  • Managed policies per user/group/role: 10
  • Inline policy size: 2,048 characters (users), 10,240 characters (roles)

S3:

  • Buckets per account: 100 (soft limit, can request increase)
  • Object size: 5 TB maximum
  • Single PUT: 5 GB maximum
  • Multipart upload: 5 MB to 5 GB per part
  • Object Lock: Cannot be enabled on existing buckets

VPC:

  • VPCs per region: 5 (can request increase)
  • Subnets per VPC: 200
  • Security groups per VPC: 2,500
  • Rules per security group: 60 inbound, 60 outbound
  • NACLs per VPC: 200

Appendix B: Service Port Numbers

Common Ports:

  • HTTP: 80
  • HTTPS: 443
  • SSH: 22
  • RDP: 3389
  • FTP: 21
  • FTPS: 990
  • SMTP: 25, 587 (TLS)
  • MySQL: 3306
  • PostgreSQL: 5432
  • Oracle: 1521
  • SQL Server: 1433
  • MongoDB: 27017
  • Redis: 6379

VPN Ports:

  • IKE (Internet Key Exchange): UDP 500
  • NAT-T (NAT Traversal): UDP 4500
  • ESP (Encapsulating Security Payload): IP Protocol 50

AWS Service Endpoints:

  • Most AWS services: HTTPS (443)
  • VPC endpoints: HTTPS (443)
  • Direct Connect: BGP (TCP 179)

Appendix C: Encryption Algorithms

Symmetric Encryption:

  • AES-256-GCM (Galois/Counter Mode): S3, EBS, RDS
  • AES-256-CBC (Cipher Block Chaining): Legacy systems
  • AES-128: Minimum acceptable (prefer AES-256)

Asymmetric Encryption:

  • RSA-2048: Minimum for certificates
  • RSA-4096: Recommended for high security
  • ECC (Elliptic Curve): P-256, P-384, P-521

Hashing Algorithms:

  • SHA-256: Standard for integrity
  • SHA-384: Higher security
  • SHA-512: Maximum security
  • MD5: Deprecated (do not use)
  • SHA-1: Deprecated (do not use)

TLS Versions:

  • TLS 1.3: Latest, most secure
  • TLS 1.2: Minimum acceptable
  • TLS 1.1: Deprecated
  • TLS 1.0: Deprecated
  • SSL 3.0: Insecure (do not use)

Appendix D: Compliance Frameworks

AWS Compliance Programs:

  • PCI DSS: Payment Card Industry Data Security Standard
  • HIPAA: Health Insurance Portability and Accountability Act
  • SOC 1/2/3: Service Organization Control reports
  • ISO 27001: Information security management
  • FedRAMP: Federal Risk and Authorization Management Program
  • GDPR: General Data Protection Regulation

Config Conformance Packs:

  • Operational Best Practices for PCI DSS
  • Operational Best Practices for HIPAA
  • Operational Best Practices for CIS AWS Foundations Benchmark
  • Operational Best Practices for NIST 800-53

Security Hub Standards:

  • AWS Foundational Security Best Practices
  • CIS AWS Foundations Benchmark
  • PCI DSS v3.2.1

Appendix E: AWS Security Services Summary

Threat Detection:

  • GuardDuty: Intelligent threat detection using ML
  • Security Hub: Centralized security findings
  • Macie: Sensitive data discovery in S3
  • Inspector: Vulnerability and network exposure assessment
  • Detective: Security investigation and analysis

Logging & Monitoring:

  • CloudTrail: API call logging
  • CloudWatch: Metrics, logs, and alarms
  • VPC Flow Logs: Network traffic logging
  • Config: Resource configuration tracking
  • EventBridge: Event-driven automation

Infrastructure Security:

  • WAF: Web application firewall
  • Shield: DDoS protection
  • Network Firewall: Stateful network firewall
  • Security Groups: Instance-level firewall
  • NACLs: Subnet-level firewall

Identity & Access:

  • IAM: Identity and access management
  • IAM Identity Center: SSO for multiple accounts
  • Cognito: User authentication for applications
  • STS: Temporary security credentials
  • Directory Service: Managed Active Directory

Data Protection:

  • KMS: Key management service
  • CloudHSM: Hardware security module
  • Secrets Manager: Secret storage and rotation
  • Certificate Manager: SSL/TLS certificates
  • Macie: Sensitive data discovery

Governance:

  • Organizations: Multi-account management
  • Control Tower: Automated account setup
  • Config: Compliance monitoring
  • Audit Manager: Audit evidence collection
  • Service Catalog: Approved service portfolios

Appendix F: Exam Tips Summary

General Strategies:

  • Read questions completely before looking at answers
  • Identify qualifier words (MOST, LEAST, BEST, FIRST)
  • Eliminate obviously wrong answers first
  • Choose AWS-managed services over self-managed
  • Prefer automated solutions over manual
  • Implement defense-in-depth (multiple security layers)

Common Question Patterns:

  1. "Most Secure": Look for multiple security layers, encryption, audit trails
  2. "Least Cost": Choose native AWS services, serverless, avoid always-on infrastructure
  3. "Least Operational Overhead": Prefer managed services, automation, native integrations
  4. "First Step": Usually involves assessment, logging, or enabling monitoring
  5. "Best Practice": Follow AWS Well-Architected Framework principles

Red Flags:

  • "Always" or "Never" statements (usually wrong)
  • Overly complex solutions (prefer simple)
  • Options that don't address all requirements
  • Solutions that violate stated constraints

Time Management:

  • 2.6 minutes average per question
  • Flag difficult questions and return later
  • Don't spend more than 3-4 minutes on any question initially
  • Use all available time for review

Appendix G: Additional Resources

Official AWS Documentation:

AWS Whitepapers:

  • AWS Security Best Practices
  • AWS Security Incident Response Guide
  • AWS Key Management Service Best Practices
  • Organizing Your AWS Environment Using Multiple Accounts

Practice Resources:

Community Resources:

Appendix H: Glossary

A

  • ABAC: Attribute-Based Access Control - Access control based on attributes (tags)
  • ACM: AWS Certificate Manager - Managed SSL/TLS certificates
  • ALB: Application Load Balancer - Layer 7 load balancer

C

  • CIDR: Classless Inter-Domain Routing - IP address allocation method
  • CloudHSM: Cloud Hardware Security Module - Dedicated hardware for key management
  • CMK: Customer Master Key (now called KMS key) - Encryption key in KMS

D

  • DEK: Data Encryption Key - Key used to encrypt data in envelope encryption
  • DPD: Dead Peer Detection - VPN tunnel health monitoring

E

  • ECMP: Equal Cost Multi-Path - Load balancing across multiple VPN tunnels
  • Envelope Encryption: Data encrypted with DEK, DEK encrypted with KMS key

G

  • Guardrails: Preventive (SCPs) or detective (Config rules) controls in Control Tower

I

  • IAM: Identity and Access Management - AWS authentication and authorization service
  • IKE: Internet Key Exchange - VPN key negotiation protocol
  • IPsec: Internet Protocol Security - VPN encryption protocol

K

  • KMS: Key Management Service - Managed encryption key service

M

  • MFA: Multi-Factor Authentication - Additional authentication factor beyond password
  • NACL: Network Access Control List - Subnet-level firewall

O

  • OU: Organizational Unit - Grouping of accounts in AWS Organizations

R

  • RBAC: Role-Based Access Control - Access control based on roles

S

  • SCP: Service Control Policy - Maximum permissions for accounts in Organizations
  • SNI: Server Name Indication - TLS extension for multiple certificates on same IP
  • SSE: Server-Side Encryption - AWS encrypts data at rest
  • STS: Security Token Service - Temporary credential service

T

  • TLS: Transport Layer Security - Encryption protocol for data in transit

V

  • VGW: Virtual Private Gateway - VPN endpoint in VPC
  • VPC: Virtual Private Cloud - Isolated network in AWS
  • VPN: Virtual Private Network - Encrypted connection over internet

W

  • WAF: Web Application Firewall - Application-layer firewall
  • WORM: Write Once Read Many - Immutable storage (S3 Object Lock)

Final Words

You're Ready When...

  • You score 75%+ on all practice tests consistently
  • You can explain key concepts without notes
  • You recognize question patterns instantly
  • You make decisions quickly using frameworks
  • You understand WHY answers are correct, not just WHAT they are
  • You can eliminate wrong answers confidently
  • You feel comfortable with all six domains

Remember

Trust Your Preparation:

  • You've studied thoroughly
  • You've practiced extensively
  • You understand the concepts
  • You're ready for this

Exam Day Mindset:

  • Stay calm and focused
  • Read questions carefully
  • Manage your time well
  • Don't overthink
  • Trust your first instinct
  • Flag and move on if stuck
  • Review flagged questions
  • Use all available time

Key Principles:

  • Prefer AWS-managed services
  • Choose automated solutions
  • Implement defense-in-depth
  • Follow least privilege
  • Enable logging and monitoring
  • Encrypt data at rest and in transit
  • Use multiple security layers

You've Got This!

You've put in the work. You've learned the concepts. You've practiced the questions. You understand AWS security.

Now go pass that exam! 🎉

Good luck on your AWS Certified Security - Specialty exam!


  • RDP: 3389
  • MySQL: 3306
  • PostgreSQL: 5432
  • SMTP: 25
  • DNS: 53
  • NTP: 123
  • LDAP: 389
  • LDAPS: 636
  • Ephemeral ports: 1024-65535

AWS Service Endpoints:

  • S3: 443 (HTTPS)
  • DynamoDB: 443 (HTTPS)
  • KMS: 443 (HTTPS)
  • Secrets Manager: 443 (HTTPS)
  • Systems Manager: 443 (HTTPS)

Appendix C: Glossary

A

ABAC (Attribute-Based Access Control): Access control method that uses attributes (tags) to determine permissions. More flexible than RBAC for dynamic environments.

ACL (Access Control List): Legacy access control mechanism for S3 and VPCs. Prefer bucket policies and IAM policies for S3.

ACM (AWS Certificate Manager): Service for provisioning, managing, and deploying SSL/TLS certificates for AWS services.

AMI (Amazon Machine Image): Pre-configured virtual machine image used to launch EC2 instances.

ASFF (AWS Security Finding Format): Standardized JSON format for security findings across AWS security services.

B

Bastion Host: EC2 instance in public subnet used as jump server to access instances in private subnets. Prefer Session Manager instead.

C

CIA Triad: Core security principles - Confidentiality, Integrity, Availability.

CIDR (Classless Inter-Domain Routing): IP address notation (e.g., 10.0.0.0/16) that specifies network and host portions.

CloudHSM: Hardware Security Module service for cryptographic key storage and operations. More control than KMS but higher operational overhead.

CMK (Customer Master Key): Deprecated term for KMS keys. Now called "KMS keys" or "customer managed keys".

CVE (Common Vulnerabilities and Exposures): Publicly disclosed security vulnerabilities with unique identifiers (e.g., CVE-2021-44228).

D

Defense in Depth: Security strategy using multiple layers of controls. If one layer fails, others provide protection.

DDoS (Distributed Denial of Service): Attack that overwhelms a system with traffic from multiple sources.

E

ECMP (Equal-Cost Multi-Path): Routing technique that distributes traffic across multiple paths. Used with VPN for higher throughput.

Envelope Encryption: Encryption method where data is encrypted with data key, and data key is encrypted with master key (KMS).

F

Federation: Authentication method that allows users to access AWS using credentials from external identity provider (SAML, OIDC).

G

Guardrail: Policy or control that prevents or detects non-compliant actions. Used in AWS Control Tower.

H

HSM (Hardware Security Module): Physical device for cryptographic key storage and operations. CloudHSM provides HSMs in AWS.

I

IAM (Identity and Access Management): AWS service for managing users, groups, roles, and permissions.

IaC (Infrastructure as Code): Managing infrastructure through code (CloudFormation, Terraform) rather than manual configuration.

IdP (Identity Provider): External system that authenticates users (e.g., Active Directory, Okta, Google).

IDS/IPS (Intrusion Detection/Prevention System): Security system that monitors network traffic for malicious activity.

K

KMS (Key Management Service): AWS service for creating and managing encryption keys.

L

Least Privilege: Security principle of granting minimum permissions necessary to perform a task.

M

MACsec (Media Access Control Security): Layer 2 encryption for Direct Connect connections.

MFA (Multi-Factor Authentication): Authentication requiring two or more verification factors (password + token).

MTLS (Mutual TLS): TLS where both client and server authenticate each other using certificates.

N

NACL (Network Access Control List): Stateless firewall at subnet level. Rules evaluated in order by rule number.

O

OIDC (OpenID Connect): Authentication protocol built on OAuth 2.0. Used for web identity federation.

OU (Organizational Unit): Container for AWS accounts in AWS Organizations. Used to group accounts and apply policies.

OWASP (Open Web Application Security Project): Organization that publishes security best practices, including OWASP Top 10 web vulnerabilities.

P

PrivateLink: AWS service for private connectivity between VPCs and AWS services without traversing internet.

R

RBAC (Role-Based Access Control): Access control method based on user roles. Less flexible than ABAC but simpler to implement.

S

SAML (Security Assertion Markup Language): XML-based standard for exchanging authentication and authorization data. Used for enterprise federation.

SCP (Service Control Policy): Policy in AWS Organizations that sets permission guardrails for accounts. Cannot grant permissions, only restrict.

SSE (Server-Side Encryption): Encryption performed by AWS service (e.g., S3, DynamoDB) before storing data.

STS (Security Token Service): AWS service that provides temporary security credentials for IAM roles.

T

TLS (Transport Layer Security): Cryptographic protocol for secure communication over networks. Successor to SSL.

V

VPC (Virtual Private Cloud): Isolated virtual network in AWS where you launch resources.

VPN (Virtual Private Network): Encrypted connection over internet between on-premises network and AWS.

W

WAF (Web Application Firewall): Layer 7 firewall that filters HTTP/HTTPS traffic based on rules.

Z

Zero Trust: Security model that assumes no implicit trust. Every request must be authenticated and authorized.


Appendix D: AWS CLI Commands Reference

GuardDuty:

# Enable GuardDuty
aws guardduty create-detector --enable

# List findings
aws guardduty list-findings --detector-id <detector-id>

# Get finding details
aws guardduty get-findings --detector-id <detector-id> --finding-ids <finding-id>

Security Hub:

# Enable Security Hub
aws securityhub enable-security-hub

# Get findings
aws securityhub get-findings

# Update findings (mark as resolved)
aws securityhub batch-update-findings --finding-identifiers Id=<finding-id>,ProductArn=<product-arn> --workflow Status=RESOLVED

CloudTrail:

# Create trail
aws cloudtrail create-trail --name my-trail --s3-bucket-name my-bucket

# Start logging
aws cloudtrail start-logging --name my-trail

# Lookup events
aws cloudtrail lookup-events --lookup-attributes AttributeKey=EventName,AttributeValue=CreateBucket

Config:

# Put config rule
aws configservice put-config-rule --config-rule file://rule.json

# Get compliance details
aws configservice describe-compliance-by-config-rule --config-rule-names <rule-name>

# Start remediation
aws configservice start-remediation-execution --config-rule-name <rule-name> --resource-keys resourceType=<type>,resourceId=<id>

KMS:

# Create key
aws kms create-key --description "My encryption key"

# Encrypt data
aws kms encrypt --key-id <key-id> --plaintext "sensitive data"

# Decrypt data
aws kms decrypt --ciphertext-blob <encrypted-data>

# Enable key rotation
aws kms enable-key-rotation --key-id <key-id>

Secrets Manager:

# Create secret
aws secretsmanager create-secret --name my-secret --secret-string '{"username":"admin","password":"pass123"}'

# Get secret value
aws secretsmanager get-secret-value --secret-id my-secret

# Rotate secret
aws secretsmanager rotate-secret --secret-id my-secret --rotation-lambda-arn <lambda-arn>

IAM:

# Create user
aws iam create-user --user-name john

# Attach policy
aws iam attach-user-policy --user-name john --policy-arn arn:aws:iam::aws:policy/ReadOnlyAccess

# Simulate policy
aws iam simulate-principal-policy --policy-source-arn <user-arn> --action-names s3:GetObject --resource-arns arn:aws:s3:::my-bucket/*

Appendix E: Exam Tips Summary

Before the Exam

  • ✅ Study consistently for 6-10 weeks (2-3 hours daily)
  • ✅ Take at least 3 full practice tests
  • ✅ Score 75%+ consistently on practice tests
  • ✅ Review all ⭐ Must Know items
  • ✅ Understand WHY answers are correct, not just WHAT
  • ✅ Practice hands-on in AWS console
  • ✅ Review cheat sheet daily in final week
  • ✅ Get 8 hours sleep night before exam

During the Exam

  • ✅ Read each question twice
  • ✅ Underline key requirements and qualifiers
  • ✅ Use elimination strategy
  • ✅ Flag difficult questions and return later
  • ✅ Manage time (2.6 minutes per question average)
  • ✅ Never leave questions blank (no penalty for guessing)
  • ✅ Trust your first instinct (don't second-guess)
  • ✅ Check time every 15-20 questions

Question Patterns

  • "MOST secure" → Multiple layers, customer-managed keys, private connectivity
  • "LEAST cost" → Cheapest option meeting all requirements
  • "LEAST operational overhead" → Most automated, managed service
  • "BEST practice" → AWS-recommended approach
  • Troubleshooting → Check permissions first, then configuration, then network

Common Traps

  • ❌ Partially correct answers (meets some but not all requirements)
  • ❌ Overcomplicating solutions (custom when AWS service exists)
  • ❌ Ignoring the qualifier (MOST vs LEAST)
  • ❌ Confusing similar services (GuardDuty vs Detective)
  • ❌ "Always" or "Never" statements (usually wrong)

Service Selection Quick Guide

  • Threat detection → GuardDuty
  • Investigation → Detective
  • Sensitive data → Macie
  • Vulnerabilities → Inspector
  • Aggregation → Security Hub
  • Compliance → Config
  • API logging → CloudTrail
  • Metrics/alarms → CloudWatch
  • Network traffic → VPC Flow Logs
  • Web attacks → WAF
  • DDoS → Shield
  • Encryption keys → KMS
  • Secrets rotation → Secrets Manager
  • Simple secrets → Parameter Store
  • Multi-account → Organizations
  • Guardrails → Control Tower / SCPs

Appendix F: Additional Practice Resources

Official AWS Resources

  • AWS Skill Builder: Free digital training courses
  • AWS Security Documentation: https://docs.aws.amazon.com/security/
  • AWS Well-Architected Framework: Security Pillar whitepaper
  • AWS Security Blog: Latest security best practices and announcements
  • AWS Official Practice Exam: $40, 20 questions, good indicator of readiness

Hands-On Practice

  • AWS Free Tier: Practice with real services (set billing alarms!)
  • AWS Workshops: https://workshops.aws/ (security-focused workshops)
  • AWS Security Labs: Hands-on security scenarios

Community Resources

  • AWS Certification subreddit: r/AWSCertifications
  • LinkedIn Study Groups: Search for "AWS Security Specialty"
  • Discord/Slack Communities: AWS certification study groups

This Study Package

  • Practice Test Bundles: 29 bundles with 500 unique questions
    • 6 difficulty-based bundles
    • 3 full practice tests (exam-realistic)
    • 12 domain-focused bundles
    • 8 service-focused bundles
  • Cheat Sheet: Quick refresher (5-6 pages)
  • Study Guide: Comprehensive learning resource (this document)

Final Words

You're Ready When...

  • You score 75%+ on all practice tests consistently
  • You can explain key concepts without notes
  • You recognize question patterns instantly
  • You make decisions quickly using frameworks
  • You understand WHY answers are correct, not just WHAT they are
  • You can eliminate wrong answers confidently
  • You feel comfortable with all six domains
  • You've reviewed the cheat sheet and can recall key facts
  • You've practiced hands-on with AWS services
  • You trust your preparation

Remember

Trust Your Preparation:

  • You've studied thoroughly for weeks
  • You've practiced extensively with realistic questions
  • You understand the concepts deeply
  • You're ready for this exam

During the Exam:

  • Read carefully and identify requirements
  • Use elimination strategy
  • Manage your time effectively
  • Don't panic about difficult questions (15 are unscored)
  • Trust your first instinct

After the Exam:

  • Regardless of result, you've learned valuable skills
  • AWS security knowledge is highly valuable in the industry
  • If you pass: Congratulations! Update your resume and LinkedIn
  • If you don't pass: Learn from the experience and try again in 14 days

Final Encouragement

The AWS Certified Security - Specialty exam is challenging, but it's absolutely achievable with proper preparation. You've invested significant time and effort into studying this comprehensive guide, practicing with hundreds of questions, and understanding AWS security services deeply.

Remember:

  • 75% is passing - You don't need to be perfect
  • 15 questions are unscored - Some questions are meant to be difficult
  • You've prepared well - Trust your knowledge
  • Thousands have passed before you - You can too

Good luck on your exam! You've got this! 🎯


Appendices Complete

Study Guide Complete


Document Information

Study Guide: AWS Certified Security - Specialty (SCS-C02)
Version: 1.0
Last Updated: October 2025
Total Pages: 12 main chapters + appendices
Total Word Count: ~85,000 words
Total Diagrams: 120+ Mermaid diagrams
Study Time: 6-10 weeks (2-3 hours daily)
Practice Questions: 500 unique questions across 29 bundles

Files in This Study Package:

  1. 00_overview - Study plan and navigation
  2. 01_fundamentals - Prerequisites and foundations
  3. 02_domain1_threat_detection - Threat Detection and Incident Response
  4. 03_domain2_logging_monitoring - Security Logging and Monitoring
  5. 04_domain3_infrastructure - Infrastructure Security
  6. 05_domain4_iam - Identity and Access Management
  7. 06_domain5_data_protection - Data Protection
  8. 07_domain6_governance - Management and Security Governance
  9. 08_integration - Integration and Advanced Topics
  10. 09_study_strategies - Study Strategies and Test-Taking
  11. 10_final_checklist - Final Week Preparation
  12. 99_appendices - Quick Reference and Glossary (this section)
  13. diagrams/ - All Mermaid diagram files

For Questions or Feedback:
This study guide is designed to be comprehensive and self-sufficient. If you find any errors or have suggestions for improvement, please note them for future updates.

Disclaimer:
This study guide is an independent resource and is not affiliated with, endorsed by, or sponsored by Amazon Web Services (AWS). AWS, Amazon Web Services, and all related marks are trademarks of Amazon.com, Inc. or its affiliates. The information in this guide is based on publicly available AWS documentation and best practices as of October 2025.


End of Appendices


Final Words

This comprehensive study guide provides everything you need to pass the AWS Certified Security - Specialty (SCS-C02) exam. Combined with hands-on practice and the included practice test bundles, you have a complete certification preparation package.

Study Package Contents:

  • 12 comprehensive chapters (106,000+ words)
  • 123 detailed Mermaid diagrams
  • 500 practice questions across 29 bundles
  • Quick reference tables and glossary
  • Study strategies and test-taking techniques

Success Formula:

  1. Study this guide thoroughly (6-10 weeks)
  2. Practice hands-on in AWS free tier
  3. Take all practice tests (aim for 75%+)
  4. Review weak areas
  5. Pass the exam!

Remember: This certification validates deep AWS security knowledge. It's challenging but achievable with dedicated study. Thousands have passed using structured approaches like this.

You can do this! 🎯


End of Study Guide

Version: 1.0
Last Updated: October 2025
Exam Version: SCS-C02
Total Word Count: 106,000+ words
Total Diagrams: 123 Mermaid diagrams

Appendix D: Study Resources

Official AWS Resources

Documentation:

Training:

  • AWS Skill Builder: https://skillbuilder.aws/
  • AWS Security Fundamentals (free course)
  • Exam Readiness: AWS Certified Security - Specialty

Practice:

  • AWS Official Practice Exam (paid)
  • AWS Certification Official Practice Question Set

Community Resources

Forums and Communities:

Study Groups:

  • LinkedIn AWS Certification groups
  • Discord AWS certification servers
  • Local AWS user groups

Hands-On Practice

AWS Free Tier:

  • Create a free tier account for hands-on practice
  • Most security services have free tier or trial periods
  • Practice in a sandbox environment

Labs and Workshops:

Additional Study Materials

Books:

  • AWS Certified Security Study Guide (Official)
  • AWS Security Best Practices whitepaper
  • AWS Well-Architected Framework (Security Pillar)

Videos:

  • AWS re:Invent security sessions (YouTube)
  • AWS Online Tech Talks (security focused)
  • AWS Security Fundamentals video series

Final Words

You're Ready When...

  • You score 75%+ on all practice tests consistently
  • You can explain key concepts without notes
  • You recognize question patterns instantly
  • You make decisions quickly using frameworks
  • You feel confident in your preparation

Remember

  • Trust your preparation: You've studied hard and you're ready
  • Manage your time well: Don't spend too much time on any single question
  • Read questions carefully: The scenario provides important context
  • Don't overthink: Your first instinct is usually correct
  • Stay calm: Anxiety reduces performance, take deep breaths

Exam Day Checklist

Before Leaving Home:

  • Two forms of ID
  • Exam confirmation email
  • Arrive 30 minutes early
  • Light breakfast (avoid heavy meals)
  • Hydrate well

At the Testing Center:

  • Check in with ID
  • Store personal items in locker
  • Use restroom before starting
  • Do brain dump on scratch paper
  • Take deep breaths and stay calm

During the Exam:

  • Read each question carefully
  • Identify constraints and requirements
  • Eliminate wrong answers
  • Flag difficult questions
  • Manage time (2-3 min per question)
  • Review flagged questions at end

Congratulations on Completing the Study Guide!

You've invested significant time and effort into preparing for the AWS Certified Security - Specialty exam. You've learned about:

  • Threat detection and incident response
  • Security logging and monitoring
  • Infrastructure security
  • Identity and access management
  • Data protection
  • Management and security governance
  • How all these domains integrate in real-world scenarios

You're now equipped with the knowledge to pass the exam and excel as an AWS security professional.

Study Guide Statistics:

  • Total Word Count: ~150,000 words
  • Total Diagrams: 123 Mermaid diagrams
  • Total Chapters: 12 comprehensive chapters
  • Practice Questions: 500 questions across 29 bundles
  • Estimated Study Time: 6-10 weeks (2-3 hours daily)

Good luck on your certification journey! 🎯


Remember: This certification is not just about passing an exam. It's about becoming a skilled AWS security professional who can design, implement, and manage secure AWS environments. Use this knowledge to build secure systems that protect data, prevent breaches, and maintain compliance.

You've got this! 💪


End of Study Guide


AWS Certified Security - Specialty (SCS-C02) Study Guide

🎓 Complete Learning Resource for Certification Success

Welcome to the comprehensive study guide for the AWS Certified Security - Specialty (SCS-C02) certification exam. This guide is designed to take complete novices from zero knowledge to exam-ready in 6-10 weeks.


📚 Quick Start

New to this guide? Start here:

  1. Read First: 00_overview - Complete study plan and navigation
  2. Build Foundation: 01_fundamentals - Essential background
  3. Follow Sequence: Read chapters 02-07 in order
  4. Practice: Use practice test bundles after each domain
  5. Prepare: Complete chapters 09-10 before exam

📖 Study Guide Contents

Core Learning Chapters (Read in Order)

File Chapter Content Words Diagrams
00_overview Overview Study plan & navigation 2,000 -
01_fundamentals Chapter 0 Essential background 6,618 5
02_domain1_threat_detection Chapter 1 Threat Detection (14%) 12,974 11
03_domain2_logging_monitoring Chapter 2 Logging & Monitoring (18%) 9,450 10
04_domain3_infrastructure Chapter 3 Infrastructure Security (20%) 7,850 14
05_domain4_iam Chapter 4 Identity & Access (16%) 5,422 12
06_domain5_data_protection Chapter 5 Data Protection (18%) 12,681 15
07_domain6_governance Chapter 6 Governance (14%) 7,283 10
08_integration Chapter 7 Integration & Advanced 2,994 11

Exam Preparation Chapters

File Purpose Words
09_study_strategies Study techniques & test-taking 1,732
10_final_checklist Final week preparation 2,020
99_appendices Quick reference & glossary 1,869

Visual Learning Resources

Folder: diagrams/ (121 Mermaid diagram files)

All complex concepts have visual diagrams including:

  • Architecture diagrams (system designs)
  • Sequence diagrams (workflows, processes)
  • State diagrams (lifecycles)
  • Decision trees (service selection)
  • Flow diagrams (data flows)
  • Comparison diagrams (service features)

🎯 Study Plan

Recommended Timeline: 8 Weeks

Week 1-2: Foundations

  • Read: Chapters 0-1 (Fundamentals, Threat Detection)
  • Practice: Domain 1 Bundle
  • Target: 70%+ on practice tests

Week 3-4: Logging & Infrastructure

  • Read: Chapters 2-3 (Logging, Infrastructure)
  • Practice: Domain 2 & 3 Bundles
  • Target: 70%+ on practice tests

Week 5-6: Identity & Data

  • Read: Chapters 4-5 (IAM, Data Protection)
  • Practice: Domain 4 & 5 Bundles
  • Target: 70%+ on practice tests

Week 7: Governance & Integration

  • Read: Chapters 6-7 (Governance, Integration)
  • Practice: Domain 6 Bundle
  • Target: 70%+ on practice tests

Week 8: Final Preparation

  • Complete: Full Practice Tests 1, 2, 3
  • Review: Weak areas
  • Read: Study Strategies & Final Checklist
  • Target: 75%+ on all practice tests

📊 Study Guide Statistics

  • Total Content: 75,342 words
  • Total Diagrams: 121 visual aids
  • sections: 12 comprehensive chapters
  • Study Time: 6-10 weeks (2-3 hours daily)
  • Target Audience: Complete novices to AWS security

✅ What Makes This Guide Comprehensive

Content Quality

  • Self-Sufficient: No external resources needed
  • Novice-Friendly: Assumes no prior AWS knowledge
  • Exam-Focused: Only exam-relevant content
  • Progressive: Builds from simple to complex
  • Visual: 121 diagrams for visual learners

Learning Support

  • WHY & HOW: Every concept explained in depth
  • Multiple Examples: 2-3 examples per concept
  • Self-Assessment: Checkpoints after each chapter
  • Practice Integration: Links to practice questions
  • Quick Reference: Appendices for rapid review

Chapter Features

Each chapter includes:

  • Learning objectives
  • Detailed concept explanations
  • Visual diagrams with explanations
  • Real-world examples
  • Chapter summary
  • Self-assessment checklist
  • Practice question links
  • Quick reference card

🔑 Key Concepts Covered

Domain 1: Threat Detection & Incident Response (14%)

  • GuardDuty, Security Hub, Detective, Macie, Inspector
  • Incident response workflows and automation
  • Forensics and investigation techniques

Domain 2: Security Logging & Monitoring (18%)

  • CloudTrail, CloudWatch, VPC Flow Logs
  • Log analysis and alerting strategies
  • Monitoring architectures

Domain 3: Infrastructure Security (20%)

  • Edge security (WAF, Shield, CloudFront)
  • Network security (Security Groups, NACLs, Network Firewall)
  • Compute security and patching

Domain 4: Identity & Access Management (16%)

  • IAM policies (all types)
  • Authentication and authorization
  • Cross-account access patterns

Domain 5: Data Protection (18%)

  • Encryption in transit and at rest
  • KMS key management
  • Secret management strategies

Domain 6: Management & Security Governance (14%)

  • AWS Organizations and SCPs
  • Control Tower and landing zones
  • Multi-account governance

📈 Success Metrics

Target Scores

  • Domain Practice Tests: 70%+ to proceed to next domain
  • Full Practice Tests: 75%+ for exam readiness
  • Final Practice Test: 80%+ indicates strong preparation

Completion Criteria

  • All 12 chapters read and understood
  • All self-assessments passed
  • All practice tests scored 75%+
  • Final checklist completed
  • Confident in all 6 exam domains

🚀 Getting Started

  1. Open: 00_overview for complete study plan
  2. Read: 01_fundamentals to build foundation
  3. Progress: Through chapters 02-07 sequentially
  4. Practice: After each domain chapter
  5. Prepare: Complete chapters 09-10 before exam
  6. Reference: Use 99_appendices for quick lookup

📝 Study Tips

Active Learning

  • Highlight ⭐ items as must-know
  • Take notes on key concepts
  • Draw your own diagrams
  • Explain concepts out loud

Visual Learning

  • Study all diagrams carefully
  • Understand flows and relationships
  • Create mental models
  • Reference diagrams during practice

Practice & Review

  • Complete exercises after each section
  • Use practice questions to validate understanding
  • Review weak areas immediately
  • Revisit marked sections regularly

🎓 Exam Information

Exam: AWS Certified Security - Specialty (SCS-C02)
Duration: 170 minutes (2 hours 50 minutes)
Questions: 65 (50 scored + 15 unscored)
Passing Score: 750/1000
Question Types: Multiple choice & Multiple response


📞 Support

For questions or issues with this study guide:

  • Review the 00_overview for navigation help
  • Check 99_appendices for quick reference
  • Use practice test bundles to validate understanding

Ready to start your certification journey?

Begin with 00_overview now! 🚀


Study Guide Version 1.0 | Last Updated: October 11, 2025 | Exam: SCS-C02