A.8.24 Use of cryptography
Define and implement rules for effective use of cryptography and key management.
13
artefacts
3
held by a system
2
at each review
hard
to go live
Policy repository / GRC workspace
where the evidence lives
teal = a system already holds it · olive = produced at each review
system holds itEvidence a system already holds
- Key Destruction Log · Key management / PKI
- Algorithm Change Request Log · SIEM / log platform
- Encrypted Data Transfer Log · SIEM / log platform
periodic reviewEvidence produced at each review
- Algorithm Risk Assessment Report · Policy repository / GRC workspace
- Key Usage Audit Report · Cloud console / configuration management
governing documentDocuments that govern the control
- Information Security Encryption Policy · Policy repository / GRC workspace
- Policy Approval Minutes · Policy repository / GRC workspace
- Policy Distribution Register · Policy repository / GRC workspace
- Key Generation Procedure Document · Policy repository / GRC workspace
- Key Rotation Schedule · Policy repository / GRC workspace
- Key Revocation Process · Policy repository / GRC workspace
- Approved Cryptographic Algorithms List · Policy repository / GRC workspace
- Key Access Control Matrix · Policy repository / GRC workspace
First move
Mostly documents and reviews. Pull the 3 system-held artefacts from your SIEM / log platform on a schedule; put the documents under version control with an owner and review date, and log each review as a dated record with a named reviewer.
Common gaps auditors find
- Missing documented key lifecycle
- Use of outdated or weak algorithms
- Inadequate segregation of duties for key handling
- Lack of regular key rotation evidence
Do this for your whole sheet
Paste the rows you run your controls from and get this mapping for every control at once, with the periodic-review ones flagged and a first move per row. No account for the first run.
Build my evidence sheet