Annex A 8.17
Clock synchronisation
Clocks of information processing systems are synchronised to approved time sources.
What an assessor looks for
Small control, disproportionate consequences. Without it, correlating logs across systems during an investigation becomes unreliable.
Where it usually fails
Most systems synchronise correctly while a few drift, which is discovered only during an investigation.
Classification
- Theme
- A.8 Technological
- Control type
- Detective
- Security properties
- Integrity
- Cybersecurity concepts
- Detect, Protect
- ISO 27001:2013 equivalent
- 12.4.4
Control number and title are identifiers used as references. The classification above is our own analysis, aligned to the shape of the ISO 27002 attribute model rather than reproduced from it, and no text from the standard appears on this page. Last reviewed 2026-08-03.
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