3.1.22
AC.L1-3.1.22 · Level 1 + 2
Control CUI posted or processed on publicly accessible systems.
NIST SP 800-171 Rev 2 · §3.1.22
Control CUI posted or processed on publicly accessible systems.
Assessment objectives
3.1.22[a]
individuals authorized to post or process information on publicly accessible systems are identified.
Examine
[SELECT FROM: Access control policy; procedures addressing publicly accessible content; security plan; list of users authorized to post publicly accessible content on organizational systems; training materials and/or records; records of publicly accessible information reviews; records of response to nonpublic information on public websites; system audit logs and records; security awareness training records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for managing publicly accessible information posted on organizational systems; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms implementing management of publicly accessible content].
3.1.22[b]
procedures to ensure CUI is not posted or processed on publicly accessible systems are identified.
Examine
[SELECT FROM: Access control policy; procedures addressing publicly accessible content; security plan; list of users authorized to post publicly accessible content on organizational systems; training materials and/or records; records of publicly accessible information reviews; records of response to nonpublic information on public websites; system audit logs and records; security awareness training records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for managing publicly accessible information posted on organizational systems; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms implementing management of publicly accessible content].
3.1.22[c]
a review process in in place prior to posting of any content to publicly accessible systems.
Examine
[SELECT FROM: Access control policy; procedures addressing publicly accessible content; security plan; list of users authorized to post publicly accessible content on organizational systems; training materials and/or records; records of publicly accessible information reviews; records of response to nonpublic information on public websites; system audit logs and records; security awareness training records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for managing publicly accessible information posted on organizational systems; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms implementing management of publicly accessible content].
3.1.22[d]
content on publicly accessible information systems is reviewed to ensure that it does not include CUI.
Examine
[SELECT FROM: Access control policy; procedures addressing publicly accessible content; security plan; list of users authorized to post publicly accessible content on organizational systems; training materials and/or records; records of publicly accessible information reviews; records of response to nonpublic information on public websites; system audit logs and records; security awareness training records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for managing publicly accessible information posted on organizational systems; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms implementing management of publicly accessible content].
3.1.22[e]
mechanisms are in place to remove and address improper posting of CUI.
Examine
[SELECT FROM: Access control policy; procedures addressing publicly accessible content; security plan; list of users authorized to post publicly accessible content on organizational systems; training materials and/or records; records of publicly accessible information reviews; records of response to nonpublic information on public websites; system audit logs and records; security awareness training records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for managing publicly accessible information posted on organizational systems; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms implementing management of publicly accessible content].
What we look for in practice
The following are placeholder notes that should be refined based on practice experience.
What assessors look for in practice. Documented evidence that this control is implemented across all CUI-handling systems within scope. Specific artifacts vary, but expect requests for written procedures, system configurations, and operational records demonstrating the control is active.
Common failure patterns. Typical issues include incomplete documentation, inconsistent implementation across systems, and missing periodic review records. Refine this section as your practice accumulates direct assessment experience.
Strong evidence looks like. Formal policy referencing this control, technical configurations demonstrating enforcement, periodic review logs with sign-off, and procedures for handling exceptions.
Scoring and POA&M context. 1-point control under the DoD Assessment Methodology. Lower scoring impact, but still required for full compliance. Not POA&M-eligible — must be implemented at assessment time.