Episode 35 — A.5.25–5.26 — Event assessment/decision; Incident response
A.5.25 establishes a disciplined mechanism to assess events and decide whether they constitute information security incidents, preventing alert fatigue and ensuring consistent prioritization. For exam purposes, distinguish between events, alerts, and incidents, and emphasize the need for defined criteria that consider asset criticality, data classification, attack indicators, and potential business impact. Triage must be timely, with clear evidence capture, escalation paths, and logging to support later analysis. The control seeks reliable, repeatable decision-making that aligns with risk appetite, legal thresholds, and communication plans so that the right resources engage at the right time.
A.5.26 governs the response once an incident is declared, specifying containment, eradication, recovery, and post-incident activities. Effective response integrates with digital forensics, crisis communications, breach notification rules, and business continuity, ensuring actions preserve evidence while restoring operations safely. In practice, teams maintain playbooks for common scenarios—ransomware, credential theft, supply-chain compromise, data exfiltration—and use predefined authority matrices for customer and regulator notifications. Pitfalls include improvisation without documentation, uncontrolled changes during recovery, and failure to learn from incidents. Mature programs operate with runbooks tied to severity levels, conduct root cause analysis, and track corrective actions to closure. Candidates should connect these controls to measurable readiness: on-call coverage, tooling for containment, secure communication channels, and structured retrospectives that improve detection rules, hardening baselines, and training content. Produced by BareMetalCyber.com, where you’ll find more cyber audio courses, books, and information to strengthen your educational path. Also, if you want to stay up to date with the latest news, visit DailyCyber.News for a newsletter you can use, and a daily podcast you can commute with.