← Assurance

Objective

The audit log has not been altered, and the limits of that statement are stated.

Assurance

automated — ARC decides this from its own records

Frequency

continuous

Severity if it fails

critical

Enabled

Yes

Category

evidence

Verify the hash chain end to end. A broken or edited chain fails. A chain that verifies against an externally recorded head passes. A chain that verifies only against itself is reported as not assessable, because walking the records cannot detect truncation: remove entries from the end and what remains is a shorter, perfectly valid chain.

• Without an externally anchored head this control cannot pass, and that is the intended behaviour rather than a defect. ARC verifying its own log against its own copy of the head proves nothing to a reader who does not trust ARC.
• The store's head marker file is defence against accidental truncation — a crash, a partial restore, a log rotation that dropped the tail. An attacker who can rewrite the log can usually rewrite that file too.

Status

Not assessable

Summary

The chain is internally consistent, but without an externally anchored head this control cannot pass: truncation is undetectable from the records alone.

Evaluated

2026-10-26 09:18:30Z

Assessment

arc_asm_55d9a5…

Covering 2026-09-26 09:18:30Z to 2026-10-26 09:18:30Z — 7 action(s) and 8 evidence record(s) fell in that window. Every status below describes that period and nothing outside it.