ISO 27001 Annex A 8.5: Secure authentication

What auditors look for

Auditors check that 8.5 is either justified as not applicable in your Statement of Applicability or implemented and working. Typical evidence includes:

• MFA enforcement reports
• Single sign-on configuration
• Authentication standard

How to implement 8.5 in practice

1. Enforce MFA for all users, starting with admins
2. Prefer phishing-resistant methods
3. Lock out or throttle repeated failures
4. Name an owner for 8.5, decide how often it runs and file evidence each time, so the control is audit-ready all year.

How 8.5 supports GDPR

This control helps demonstrate GDPR Art. 32. Map it once in your control matrix so the same evidence supports both ISO 27001 and GDPR accountability. See the GDPR compliance checklist.

Recording 8.5 in the Statement of Applicability

List 8.5 with whether it applies, the reason (usually the risks it treats or a legal or contractual requirement), its implementation status and where the evidence lives. If you exclude it, explain why none of your risks or obligations require it.

Free resources

• ISO 27001 and GDPR readiness assessment
• 10 steps to implement ISO 27001
• Remote ISO 27001 consultant

More technological controls

• 8.1 User endpoint devices
• 8.2 Privileged access rights
• 8.3 Information access restriction
• 8.4 Access to source code
• 8.6 Capacity management
• 8.7 Protection against malware
• 8.8 Management of technical vulnerabilities
• 8.9 Configuration management