EvidenceSheet

3.7.7 Prevent unauthorised substitution of keys

Key management policies prevent unauthorized substitution of cryptographic keys.

5
artefacts
1
held by a system
1
at each review
hard
to go live
Document repository
where the evidence lives
teal = a system already holds it · olive = produced at each review

system holds itEvidence a system already holds

  • Logs of key replacement events · SIEM / log platform

periodic reviewEvidence produced at each review

  • Dual approval evidence · Document repository

governing documentDocuments that govern the control

  • Approval workflow for key changes · Document repository
  • Integrity verification mechanism · Document repository
  • Reconciliation reports · Document repository

First move

Mostly documents and reviews. Pull the 1 system-held artefact 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

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

3.7.6 Manual cleartext key operations use split knowledge · 3.7.8 Custodians acknowledge responsibilities