Implementing ISO 27001 Annex A 5.29 is the strategic process of ensuring information security controls remain effective during technical disruption or disaster recovery. The primary implementation requirement involves defining and verifying a specific security baseline for emergency operations, delivering the business benefit of continuous data protection and minimized risk exposure when operating in crisis modes.
ISO 27001 Annex A Information security during disruption Implementation Checklist
Use this implementation checklist to achieve compliance with ISO 27001 Annex A 5.29. Compliance requires you to demonstrate that your information security controls remain effective, or are adequately compensated for, when your organisation is operating in a crisis or disaster recovery mode.
1. Define the Minimum Security Baseline for Disruption
Control Requirement: The organisation must determine the level of information security required during a disruption.
Required Implementation Step: Open your Business Continuity Plan (BCP) and insert a specific “Security Baseline” section. You must explicitly list which security controls (e.g., MFA, VPN, Endpoint Protection) are non-negotiable and must remain active even when running on backup infrastructure.
Minimum Requirement: A defined list of “Critical Security Controls” within the BCP documentation.
2. Verify Patch Parity for Standby Systems
Control Requirement: Information security must be maintained at an equivalent level on alternative processing sites.
Required Implementation Step: Log in to your warm or cold standby servers and manually verify the OS and application patch levels. You must ensure that dormant Disaster Recovery (DR) hardware has not drifted behind the production environment, leaving it vulnerable to exploits the moment it is activated.
Minimum Requirement: A patch comparison report showing identical versions between Production and DR servers.
3. Replicate Firewall and ACL Configurations
Control Requirement: Network security perimeters must be maintained during a failover.
Required Implementation Step: Export the configuration files from your primary firewalls and compare them against the secondary site’s network gear using a “diff” tool. You must ensure that Access Control Lists (ACLs) and VLAN tagging rules are identical so that failover does not result in an “allow all” default state.
Minimum Requirement: Evidence of a configuration audit matching rulesets across primary and secondary locations.
4. Establish Secure Emergency Communication Channels
Control Requirement: Communication during a disruption must remain secure.
Required Implementation Step: Provision an out-of-band communication method (e.g., Signal, Wire, or satellite phones) for the Crisis Management Team. Do not rely on corporate email; you must have a pre-tested, encrypted channel that operates independently of your primary infrastructure.
Minimum Requirement: A documented and tested “Secondary Comms” procedure with verifying call logs.
5. Define “Break Glass” Access Procedures
Control Requirement: Access control must be managed securely even when standard authentication servers are unavailable.
Required Implementation Step: Create a physical or digital vault containing emergency local administrator passwords. You must document a strict procedure for accessing these credentials that includes dual-control (requires two people) to prevent abuse during the chaos of an outage.
Minimum Requirement: A sealed “Break Glass” envelope or vault log showing who accessed emergency credentials and why.
6. Configure Local Logging for Disconnected States
Control Requirement: Security monitoring must continue even if the central SIEM is unreachable.
Required Implementation Step: Configure your critical servers to cache logs locally or forward them to a local collector at the DR site. You must ensure that if the link to the primary Security Operations Centre (SOC) is severed, forensic evidence is still being generated and stored.
Minimum Requirement: A test log file generated and stored locally on a DR asset during a network isolation test.
7. Test Security Controls During BC Exercises
Control Requirement: The effectiveness of security controls during disruption must be verified.
Required Implementation Step: During your annual Business Continuity test, assign a security analyst to run a vulnerability scan or penetration test against the active DR environment. You must prove that the failover environment is not just functional, but also hardened.
Minimum Requirement: A vulnerability scan report generated specifically from the DR environment during a live exercise.
8. Secure the Hardcopy Fallback Process
Control Requirement: Information security must extend to manual or paper-based workarounds.
Required Implementation Step: If your BCP calls for using pen and paper, distribute cross-cut shredders and lockable storage bins to the temporary workspace. You must ensure that sensitive physical records generated during the outage are not left unsecured on desks.
Minimum Requirement: Physical inspection logs of the temporary command centre confirming secure disposal facilities are present.
9. Scan Data Integrity Before Repatriation
Control Requirement: The return to normal operations must not introduce compromised data.
Required Implementation Step: Before failing back to the primary site, scan all data created or modified during the disruption for malware. You must ensure that you are not syncing infected files from the less-secure emergency environment back into the clean production network.
Minimum Requirement: A malware scan report covering all “delta data” generated during the disruption period.
10. Conduct Post-Disruption Security Review
Control Requirement: Lessons learned regarding security performance must be captured.
Required Implementation Step: Convene a specific security debrief following any test or actual incident. Review the audit trails to determine if any emergency privileges were excessive or if any security controls failed to start, and update the BCP accordingly.
Minimum Requirement: Minutes from the post-test review explicitly discussing “Security Control Performance”.
ISO 27001 Annex A 5.29 SaaS / GRC Platform Implementation Failure Checklist
| Control Requirement | The ‘Checkbox Compliance’ Trap | The Reality Check |
|---|---|---|
| Patch Parity | Storing a PDF list of assets in the GRC tool. | You need a manual terminal check (uname -a) on the DR box to prove it hasn’t been forgotten. |
| Firewall Replication | Uploading a network diagram to the “Evidence” tab. | Real compliance is a line-by-line diff of the iptables or firewall config files. |
| Break Glass Access | A policy document saying “We have emergency accounts”. | Auditors need to see the physical log of the sealed envelope or the audit trail of the PAM vault. |
| Testing Security | Marking “BCP Test Complete” on a dashboard. | You must run Nmap or Nessus against the DR site while it is live to prove it is secure. |
| Local Logging | Assuming the cloud agent handles logging everywhere. | If the internet cuts, the agent fails. You need local Syslog configuration verification. |
| Secure Repatriation | Clicking “Sync” to restore data after an outage. | Without a malware scan, you risk infecting the primary site with data from the emergency chaos. |
| Hardcopy Security | Ignoring physical security because “we are a SaaS company”. | If the internet dies and you use paper, you are legally liable for that paper’s disposal. |
| Emergency Comms | Listing “Personal Gmail” as the backup plan. | You need a pre-configured, encrypted app (e.g., Signal) to prevent data leakage during a panic. |
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