ISO 27001 A.5.24 - Information Security Incident Management Planning and Preparation

Requirement

“The organization shall plan and prepare for managing information security incidents by defining, establishing and communicating information security incident management processes, roles and responsibilities.”

Plain-language meaning

The organization must prepare before incidents happen. It needs defined and communicated incident management processes, roles, responsibilities, escalation paths, and recovery coordination.

This control is about readiness. It is not enough to react informally when something goes wrong.

Why this matters

Information security incidents can affect confidentiality, integrity, availability, safety, compliance, finances, and reputation.

Examples:

• fire or flood affecting facilities;
• power failure or hardware breakdown;
• malware or ransomware infection;
• unauthorized access attempt or confirmed compromise;
• corrupted or lost data;
• misdirected email containing sensitive information;
• failed security control;
• cloud or supplier incident affecting services;
• system failure that triggers recovery procedures.

Incident response also creates learning. A handled incident should improve procedures, controls, training, and risk treatment.

Implementation guidance

1. Define the incident management process

The process should cover:

• event and weakness reporting;
• triage and classification;
• escalation criteria;
• investigation;
• containment;
• eradication;
• recovery;
• communication;
• evidence preservation;
• legal/regulatory notification assessment;
• post-incident review;
• corrective action and improvement.

2. Define roles and responsibilities

Incident roles should be defined before an incident.

Typical roles:

3. Communicate reporting routes

Personnel should know how to report suspected incidents and weaknesses. Reporting should work for employees, contractors, suppliers, and relevant third parties.

Examples:

• security mailbox;
• service desk category;
• hotline or escalation channel;
• supplier incident contact;
• manager escalation path.

4. Prepare for likely scenarios

Plans should be compatible with likely reporting scenarios, not generic documents.

Scenario examples:

• ransomware;
• suspected account compromise;
• data leakage or misdirected email;
• lost device;
• cloud provider incident;
• supplier breach;
• system outage with security impact;
• failed backup or data corruption.

5. Connect incident response to recovery and improvement

Incident management should trigger:

• recovery procedures where needed;
• risk reassessment;
• corrective actions;
• control improvements;
• management review inputs;
• lessons learned and awareness updates.

Audit guidance

Auditors should verify that incident management is planned, communicated, and ready to operate.

Audit tests:

• review incident management policy/procedure/playbook;
• verify roles and responsibilities are defined;
• check communication and reporting channels;
• sample reported events and weaknesses;
• verify triage, investigation, escalation, recovery, and closure records;
• check whether senior roles are involved when impact requires it;
• review incident exercises or tabletop tests;
• verify corrective actions and lessons learned;
• check supplier/cloud incident integration;
• verify management review receives incident trends or significant incidents.

Auditors should reject a process that exists only as an untested document with no reporting route, role clarity, or sample records.

Evidence examples

Strong evidence

• Incident process includes triage, escalation, investigation, recovery, communication, and review.
• Roles have named owners or accountable functions.
• Personnel know how to report events and weaknesses.
• Sample incidents show review, action, closure, and lessons learned.
• Exercises test likely scenarios.
• Incidents trigger risk review and corrective action.
• Supplier/cloud incident notifications are integrated.

Weak evidence

• Incident plan exists but no one knows how to report.
• Roles are generic or unassigned.
• Incidents are handled only in chat with no record.
• No criteria for escalation or senior involvement.
• No post-incident review.
• No evidence of exercises.
• Failed controls are fixed locally but not linked to risk or corrective action.

Common failures

Exam traps

• A.5.24 is about planning and preparation, not only incident response execution.
• Incidents can affect confidentiality, integrity, or availability.
• Events and weaknesses should be reviewed and investigated where appropriate.
• Recovery procedures and senior review may need to be triggered.
• Incident management should improve the ISMS through lessons learned and corrective action.
• A plan that is not communicated is weak.

Related controls and concepts

• A.5.7 Threat Intelligence
• A.5.23 Information Security for Use of Cloud Services
• A.5.22 Monitoring, Review and Change Management of Supplier Services
• Risk Assessment
• Internal Audit
• Management Review
• Corrective Action Tracker
• Management Review Input Checklist

KB-ready summary

A.5.24 requires the organization to plan and prepare for information security incidents by defining, establishing, and communicating incident management processes, roles, and responsibilities. Practical readiness includes reporting channels, triage, escalation, investigation, recovery, communication, evidence handling, exercises, lessons learned, and corrective action.

Templates and checklists

• Incident Management Plan
• Incident Roles and Communications Matrix
• Corrective Action Tracker
• A.5.24 Audit Checklist