ISO/IEC 27001:2022 · Technological control
ISO 27001 Annex A 8.24: Use of cryptography
Quick answer
ISO 27001 Annex A 8.24 (Use of cryptography) is a technological control. Define and apply rules for effective use of cryptography, including key management.
What auditors look for
Auditors check that 8.24 is either justified as not applicable in your Statement of Applicability or implemented and working. Typical evidence includes:
- Cryptography standard
- TLS and encryption configurations
- Key management procedures
How to implement 8.24 in practice
- Use current algorithms and TLS 1.2 or later
- Manage keys separately from data
- Track certificate expiry
- Name an owner for 8.24, decide how often it runs and file evidence each time, so the control is audit-ready all year.
How 8.24 supports GDPR
This control helps demonstrate GDPR Art. 32(1)(a). Map it once in your control matrix so the same evidence supports both ISO 27001 and GDPR accountability. See the GDPR compliance checklist.
Recording 8.24 in the Statement of Applicability
List 8.24 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.