What evidence do auditors commonly ask for on AU.L2-3.3.1 System Auditing?

Defined auditable event list and rationale for its scope; Logging configuration on in scope systems; Retention settings and evidence logs are retained for the defined period; Sample audit records showing captured content.

What is the most common gap auditors find on AU.L2-3.3.1?

Logging enabled with default event sets never assessed for sufficiency

CMMC 2.0 · Audit and Accountability

`AU.L2-3.3.1` System Auditing

Generate and retain system audit logs in sufficient scope and detail to support monitoring, analysis, investigation and reporting of unlawful or unauthorized system activity.

Source: CMMC 2.0, AU.L2-3.3.1. The statement above is our statement of the clause, read from the published text and cited so you can check it against the official text, not the instrument verbatim. Open CMMC 2.0 in the compliance library.

artefacts

held by a system

at each review

easy

to go live

SIEM / log platform

where the evidence lives

teal = a system already holds it · olive = produced at each review. To go live: easy when half or more of the artefacts are already held by a system, moderate from a quarter to a half, hard below a quarter.

These are the artefacts auditors commonly ask for on this requirement, our guidance rather than text from the standard. Your assessor decides what is sufficient in your context, and asks for samples across the period when a report covers one.

system holds itEvidence a system already holds

Logging configuration on in scope systems · SIEM / log platform
Retention settings and evidence logs are retained for the defined period · SIEM / log platform

periodic reviewEvidence produced at each review

Sample audit records showing captured content · Policy repository / GRC workspace

governing documentDocuments that govern the control

Defined auditable event list and rationale for its scope · Policy repository / GRC workspace

First move

Automate the pull from your SIEM / log platform. Retention and alert rules exported from the SIEM; review evidence is the closed-alert record with reviewer and time.

Common gaps auditors find

Logging enabled with default event sets never assessed for sufficiency
Retention shorter than investigation needs
In scope systems missing from logging coverage

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

AT.L2-3.2.3 Insider Threat Awareness · AU.L2-3.3.2 User Accountability