Incident Response

Incident response (IR) is a structured methodology for handling security breaches, cyberattacks, and other security events. An effective incident response capability enables organizations to quickly detect threats, contain their impact, eradicate the root cause, recover normal operations, and learn from the experience to prevent future incidents. Without a well-defined IR process, organizations often respond to incidents in an ad hoc manner, leading to greater damage and longer recovery times.

The NIST Incident Response Lifecycle defines four phases: Preparation, Detection and Analysis, Containment Eradication and Recovery, and Post-Incident Activity. The SANS Institute uses a six-phase model: Preparation, Identification, Containment, Eradication, Recovery, and Lessons Learned. Both frameworks emphasize the importance of preparation, including developing an incident response plan, building a response team, and conducting regular exercises.

A Computer Security Incident Response Team (CSIRT) or Incident Response Team (IRT) is typically responsible for executing the incident response plan. This cross-functional team includes security analysts, forensic investigators, IT operations staff, communications specialists, and legal counsel. For major incidents, executive leadership and external parties such as law enforcement or regulatory bodies may also be involved.

Key metrics for measuring incident response effectiveness include Mean Time to Detect (MTTD), Mean Time to Respond (MTTR), and Mean Time to Contain (MTTC). Organizations improve these metrics through regular incident response exercises, tabletop simulations, automation of repetitive tasks via SOAR platforms, and continuous refinement of playbooks based on lessons learned from previous incidents.