🎯 20% of CySA+ CS0-003 Exam

CySA+ Domain 3:
Incident Response

Master incident response practices for the CompTIA CySA+ CS0-003 exam. Learn the IR lifecycle, forensic tools, playbooks, and effective incident handling strategies.

📊 Domain Overview

📈 IR Lifecycle Phases

Preparation 20%
Detection & Analysis 30%
Containment 20%
Eradication & Recovery 20%
Post-Incident Activities 10%

🎯 Learning Objectives

  • Understand the complete IR lifecycle
  • Master forensic tools and techniques
  • Learn effective containment strategies
  • Develop incident handling playbooks

📋 Incident Response Lifecycle

The Incident Response lifecycle provides a structured approach to handling cybersecurity incidents. Understanding each phase is crucial for effective incident management and minimizing damage.

1. Preparation

Develop policies, plans, and communication procedures. Establish an incident response team and ensure proper training.

  • Create incident response playbooks
  • Define roles and responsibilities
  • Establish communication channels
  • Conduct regular training and tabletop exercises

2. Detection & Analysis

Monitor logs, identify indicators of compromise (IOCs), and determine the scope and impact of incidents.

  • Analyze SIEM alerts and logs
  • Investigate suspicious activities
  • Determine incident severity and classification
  • Document findings and evidence

3. Containment

Isolate affected devices to prevent spread while preserving evidence for analysis.

  • Implement short-term containment
  • Network segmentation and isolation
  • System quarantine procedures
  • Evidence preservation and chain of custody

4. Eradication & Recovery

Remove threats completely and restore systems to normal operations with enhanced security.

  • Remove malware and threats
  • Patch vulnerabilities
  • Restore systems from clean backups
  • Implement additional security controls

5. Post-Incident Activities

Conduct lessons learned sessions, root cause analysis, and update procedures based on findings.

  • Document the incident thoroughly
  • Perform root cause analysis
  • Update incident response procedures
  • Provide regulatory reporting if required

🔐 Key Incident Response Terms

Understanding key terms is essential for mastering the Incident Response domain. These terms form the foundation of effective incident handling.

Chain of Custody

Tracks the handling of evidence through each stage of the investigation. Maintaining an unbroken chain ensures evidence integrity and admissibility in legal proceedings.

SANS Evidence Collection Guide →

Incident Response Playbook

Predefined response procedures for specific incident types. For example, a ransomware playbook may include steps for isolating affected systems, identifying encryption methods, and notifying stakeholders.

CIS Incident Response Playbooks →

Mean Time to Detect (MTTD)

The average time it takes to discover an incident. Lowering MTTD is critical for minimizing damage. Tools like Splunk and ELK Stack can help reduce detection times through automated monitoring.

Mean Time to Respond (MTTR)

The average time it takes to resolve an incident. Automation tools like Cortex XSOAR can significantly reduce MTTR by streamlining response workflows and automating routine tasks.

🛠️ Essential IR Tools & Techniques

Effective incident response requires the right tools for each phase of the lifecycle. Here are the essential categories and recommended tools for comprehensive IR capabilities.

🔬 Forensic & Analysis Tools

FTK Imager

Create forensic disk images with integrity verification

Learn More →

Autopsy

GUI forensics suite for analyzing disk images

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Wireshark

Industry-standard packet analyzer for network traffic

Learn More →

📊 SIEM & Monitoring

Splunk

Popular SIEM for log aggregation and correlation

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ELK Stack

Open-source log management and analysis suite

Learn More →

Zeek (Bro)

Network analysis framework for behavior monitoring

Learn More →

🦠 Malware Analysis

Cuckoo Sandbox

Automated malware analysis in virtual environments

Learn More →

Any.Run

Interactive online malware sandbox

Learn More →

🤖 Automation & Orchestration

Cortex XSOAR

Security orchestration and automated response

Learn More →

IBM Security SOAR

Enterprise security orchestration platform

Learn More →