CyberGlossary

Forensics & IR

Incident Response

Also known as: IR, Cyber incident response

Definition

The organised process of preparing for, detecting, analysing, containing, eradicating, and recovering from cyber security incidents, then capturing lessons learned.

Incident response (IR) is the structured response to events that compromise — or threaten to compromise — the confidentiality, integrity or availability of information assets. NIST SP 800-61 defines a six-phase lifecycle (preparation, detection and analysis, containment, eradication, recovery, post-incident activity) while SANS uses a similar PICERL model. Effective IR depends on tested playbooks, on-call rotations, communication trees, legal and PR engagement, and tools such as SIEM, SOAR, EDR, and forensic triage suites. The goal is to minimise damage and recovery time and to feed improvements back into prevention and detection.

Examples

  • Containing a confirmed business email compromise by revoking tokens, resetting credentials, and notifying impacted parties.
  • Coordinating eradication and recovery of a ransomware-infected ERP system across IT, legal, and executive teams.

Related terms