Incident Response Playbook for Windows Intrusion Detection (Updated 2025)

This Incident Response Playbook provides a step-by-step methodology for detecting, containing, remediating, and recovering from a Windows-based intrusion. It has been updated to reflect current cybersecurity practices and incorporates the use of advanced tools such as Endpoint Detection and Response (EDR), memory forensics, and threat intelligence.

1. Preparation

Objective: Ensure readiness to handle a Windows intrusion by setting up security tools, contacts, and procedures.

Key Steps:

1. Deploy Security Tools:

   • Implement EDR solutions on all endpoints and servers.

   • Ensure antivirus, IDS/IPS, and log analysis tools are operational and updated.

   • Maintain acquisition tools like FastIR, KAPE, and DFIR Orc.

2. Define Procedures:

   • Create and distribute clear incident response protocols.

   • Establish communication lines with internal teams (SOC, IT, Legal, etc.) and external partners (CERT, law enforcement).

3. Document the Environment:

   • Maintain updated records of network architecture, system configurations, and usual activities on critical servers.

   • Use a secure repository to store known services and applications running on systems.

4. Set Monitoring Baselines:

   • Define normal behaviour patterns for system activities, including network traffic, user access, and running services.

2. Identification

Objective: Detect the intrusion, determine its scope, and involve appropriate stakeholders.

Steps:

1. Evidence Acquisition:

   • Capture volatile memory before taking further actions using tools like FTK Imager or WinPmem.

   • Create a triage image with tools such as FastIR or KAPE.

2. Memory and System Analysis:

   • Investigate suspicious processes, code injections, and rootkits.

   • Analyse network artifacts, including active connections and unusual traffic patterns.

   • Use Volatility or similar tools for in-depth memory forensics.

3. Identify Persistence Mechanisms:

   • Inspect for common persistence techniques, including:

     • Scheduled tasks.

     • Startup registry keys.

     • DLL search order hijacking.

     • Service creation or replacement.

   • Use Microsoft Autoruns to quickly detect auto-start programs.

4. Review Event Logs:

   • Analyse logs for:

     • Unusual account logins (e.g., from off-hours or foreign IPs).

     • Creation of suspicious services or scheduled tasks.

     • Remote Desktop Protocol (RDP) and SMB activity.

5. Generate a Super-Timeline:

   • Use tools like Log2timeline to generate a timeline of events.

   • Analyse the timeline for key events related to the intrusion.

3. Containment

Objective: Limit the impact of the intrusion by isolating affected systems and preventing further spread.

Steps:

1. Isolate Systems:

   • If possible, disconnect infected systems from the network.

   • Use EDR to quarantine compromised endpoints remotely.

2. Backup Critical Data:

   • Back up important business data to secure storage if the system must remain operational during the investigation.

3. Prevent Further Access:

   • Implement network access control (NAC) to restrict lateral movement.

   • Block malicious IPs, URLs, or domains identified during the investigation.

4. Identify and Mitigate Attack Vectors:

   • Determine how the attacker gained access (e.g., phishing, remote exploit).

   • Apply security patches to vulnerable systems.

4. Remediation

Objective: Eliminate the threat and ensure that all traces of the attacker are removed from the environment.

Steps:

1. Apply Comprehensive Remediation:

   • Reimage Compromised Systems: Where feasible, reinstall the operating system from secure media.

   • Remove Malicious Files: Delete any malware, backdoors, or modified system files.

2. Revoke Compromised Access:

   • Disable and reset passwords for affected accounts.

   • Review and update access permissions to critical resources.

3. Apply Security Enhancements:

   • Implement application whitelisting and stronger access controls.

   • Enable EDR prevention mode and deploy updated IOC detection rules.

4. Test and Validate:

   • Ensure that the remediation steps have fully eradicated the threat.

   • Perform a system scan using antivirus, YARA rules, and other security tools to confirm no malicious activity remains.

5. Recovery

Objective: Restore systems to secure, normal operations and verify that no vulnerabilities remain.

Steps:

1. Restore Systems:

   • Fully reinstall compromised systems if possible, applying all security patches and updates.

   • Restore altered or corrupted files from clean backups.

2. Secure Account Credentials:

   • Change all passwords for local and domain accounts.

   • Implement multi-factor authentication (MFA) for critical systems.

3. Validate Recovery:

   • Monitor logs and security alerts to detect any signs of reinfection.

   • Conduct a network scan to ensure no compromised devices remain.

6. Lessons Learned

Objective: Document the incident, identify areas for improvement, and update security policies.

Steps:

1. Incident Report:

   • Document all relevant details, including:

     • Initial detection and timeline of events.

     • Actions taken during containment, remediation, and recovery.

     • Indicators of compromise (IOCs) and attack vectors.

2. Root Cause Analysis:

   • Identify how the attacker gained access and why the intrusion was not detected earlier.

   • Assess whether existing controls were bypassed or insufficient.

3. Process Improvements:

   • Update incident response playbooks based on lessons learned.

   • Implement additional security measures to prevent similar incidents.

4. Training and Awareness:

   • Conduct security awareness training for employees, focusing on the intrusion's root cause (e.g., phishing or weak passwords).

   • Provide SOC analysts with updated threat detection scenarios and simulations.

Conclusion

This Windows Intrusion Detection Playbook equips SOC teams with a structured approach to handling security incidents involving compromised Windows systems. By following these updated steps, organisations can minimise downtime, mitigate risks, and strengthen their overall security posture. Regular testing and refinement of the playbook will ensure continued effectiveness in an evolving threat landscape.

If you require additional resources, such as report templates, IOC databases, or integration guides for security tools, please reach out!