What evidence do auditors commonly ask for on AC-11 Device Lock?

Access control policy; Procedures addressing session lock; Procedures addressing identification and authentication; System design documentation; System configuration settings and associated documentation; Security plan.

What is the most common gap auditors find on AC-11?

Device lock after the organization-defined inactivity period is not configured on all endpoints, and users can disable it locally

NIST SP 800-53 Rev 5 · AC - Access Control

`AC-11` Device Lock

a. Prevent further access to the system by Selection (one or more): initiating a device lock after [organization-defined time period of inactivity; requiring the user to initiate a device lock before leaving the system unattended]; and b. Retain the device lock until the user reestablishes access using established identification and authentication procedures.

Source: NIST SP 800-53 Rev 5, AC-11. 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 NIST SP 800-53 Rev 5 in the compliance library.

Base controls and their enhancements. Which apply follows the baseline you are assessed against (for example FedRAMP Moderate or High, or the low, moderate and high baselines of SP 800-53B). Text in square brackets is a parameter your organisation sets.

artefacts

held by a system

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. 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

none for this control

periodic reviewEvidence produced at each review

Test of Mechanisms implementing access control policy for session lock · Identity provider / directory

governing documentDocuments that govern the control

Access control policy · Policy repository / GRC workspace
Procedures addressing session lock · Policy repository / GRC workspace
Procedures addressing identification and authentication · Policy repository / GRC workspace
System design documentation · Policy repository / GRC workspace
System configuration settings and associated documentation · Policy repository / GRC workspace
Security plan · Policy repository / GRC workspace
System security plan · Policy repository / GRC workspace

First move

No system holds this evidence for you: it is people and documents. Reminders and routing to the owner still save time. Put the document under version control with an owner and review date, and log each review as a record with reviewer and date.

Common gaps auditors find

Device lock after the organization-defined inactivity period is not configured on all endpoints, and users can disable it locally
The device lock under b can be cleared without reauthentication, so access resumes without established identification procedures

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

AC-10 Concurrent Session Control · AC-11(1) Device Lock | Pattern-hiding Displays