ISO 27001:2022 Annex A Control 5.26 – Response to Information Security Incidents

When an information security incident occurs, a swift, structured, and effective response can mean the difference between containment and catastrophe. ISO 27001:2022 Annex A Control 5.26 provides a framework for responding to such incidents, ensuring organisations can mitigate threats, minimise damage, and address root causes effectively.

What Is ISO 27001:2022 Annex A Control 5.26?

Annex A Control 5.26 outlines procedures for responding to information security incidents, events, and weaknesses. Its primary aim is to ensure that incidents are resolved efficiently and systematically, with all necessary personnel and resources engaged.

By implementing this control, organisations can:

• Contain and mitigate threats.
• Maintain compliance with internal and external obligations.
• Learn from incidents to prevent future occurrences.

This control builds on the foundation established in Annex A Control 5.24, which focuses on incident management planning and preparation.

Purpose of ISO 27001:2022 Annex A Control 5.26

The goal of Annex A Control 5.26 is to ensure a consistent, effective response to information security incidents. It helps organisations:

1. Minimise operational and financial damage caused by incidents.
2. Protect sensitive information and maintain business continuity.
3. Establish accountability and improve incident resolution through clear procedures and roles.
4. Identify and address vulnerabilities that caused the incident.

Ownership of Annex A Control 5.26

Ownership of Annex A Control 5.26 should rest with a senior management team member responsible for overseeing incident management activities, such as the Chief Operating Officer (COO).

This individual must:

• Ensure all personnel involved in incident response are competent and follow published processes.
• Drive performance and oversee the resolution of incidents.
• Maintain direct or indirect control over teams handling incidents to minimise errors and delays.

Implementing ISO 27001:2022 Annex A Control 5.26

To implement Annex A Control 5.26, organisations must establish robust procedures for responding to information security incidents. The following steps can guide implementation:

1. Form an Incident Response Team

• Assemble a team of trained personnel with the necessary skills to handle incidents competently.
• Ensure all team members have access to procedure documentation and receive regular training updates.

2. Contain and Mitigate Threats

• Develop protocols to contain threats and prevent further escalation.
• Use tools and techniques to isolate affected systems, block malicious activity, and secure data.

3. Gather and Preserve Evidence

• Collect and corroborate evidence immediately after an incident.
• Follow forensic best practices to ensure evidence is admissible and tamper-proof (see Annex A Control 5.28).

4. Escalate When Necessary

• Establish escalation procedures for crisis management and business continuity (see Annex A Controls 5.29 and 5.30).
• Define criteria for when and how to escalate incidents based on severity and impact.

5. Log Incident-Related Activity

• Maintain accurate records of all incident-related actions, including initial detection, response steps, and resolution.
• Ensure logs are easily accessible for audits and future analysis.

6. Communicate Using the “Need-to-Know” Principle

• Limit incident-related communications to those who need to know, including internal stakeholders and external regulators or clients.
• Be mindful of contractual and regulatory obligations when sharing information.

7. Perform Post-Mortem Analysis

• Identify the root cause of the incident and document findings for review (see Annex A Control 5.27).
• Communicate results to relevant parties and update policies or processes as needed.

8. Address Underlying Vulnerabilities

• Implement changes to processes, controls, and policies to eliminate vulnerabilities exposed by the incident.
• Use lessons learned to enhance overall security measures.

Key Principles for Effective Incident Response

Annex A Control 5.26 identifies several principles to guide incident response efforts:

Principle Description Containment Prevent the spread of threats by isolating affected systems or networks.

‍Collaboration Ensure internal and external stakeholders work together effectively to resolve incidents.

‍Accountability Assign clear roles and responsibilities to incident response team members.

‍Transparency Maintain detailed logs of all actions taken to address the incident.

‍Continuous Improvement Perform post-incident reviews to identify weaknesses and enhance future response efforts.

Supporting Annex A Controls

Annex A Control 5.26 aligns with other ISO 27001 controls to create a cohesive incident management strategy:

• 5.24: Planning and preparation for information security incidents.
• 5.27: Learning from incidents and implementing improvements.
• 5.28: Evidence handling and forensic analysis.
• 5.29 & 5.30: Crisis management and business continuity planning.

Changes from ISO 27001:2013

ISO 27001:2022 Annex A Control 5.26 replaces ISO 27001:2013 Annex A 16.1.5 with expanded guidance on:

1. Containment and Mitigation: Emphasising immediate action to minimise the impact of threats.
2. Crisis Management and Continuity: Introducing escalation procedures for severe incidents requiring organisational-level intervention.
3. Root Cause Identification: Highlighting the need to document and share findings with relevant stakeholders.
4. Process and Policy Updates: Recommending modifications to address vulnerabilities and prevent recurrence.

Additionally, Annex A Control 5.26 shifts focus from returning to a “normal security level” to achieving an optimised, resilient state post-incident.

How Harpe Can Help Implement ISO 27001:2022 Annex A Control 5.26

Managing incident response effectively can be challenging, especially for organisations with limited resources. Harpe.io simplifies this process with tools designed to support every stage of incident response, including:

• Incident Tracking and Logging: Harpe.io provides a centralised platform for recording all incident-related activities, ensuring transparency and audit readiness.
• Team Collaboration: Enable seamless communication between internal and external stakeholders, ensuring swift and coordinated responses.
• Root Cause Analysis Tools: Use built-in analytics to identify vulnerabilities and recommend process improvements.
• Policy and Procedure Updates: Manage updates to controls, policies, and processes directly within Harpe.io to ensure continuous compliance.

Conclusion

ISO 27001:2022 Annex A Control 5.26 ensures that organisations can respond effectively to information security incidents, minimising impact and preventing future occurrences. By implementing structured response procedures, collaborating with stakeholders, and addressing root causes, organisations can enhance their resilience to security threats.

With Harpe, managing incident response becomes more efficient, collaborative, and compliant with ISO 27001 standards. Ready to strengthen your incident response capabilities? Get started with Harpe today!