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Controls / Security Assessment / 3.12.1
3.12.1
CA.L2-3.12.1 · Level 2

Periodically assess the security controls in organizational systems to determine if the controls…

NIST SP 800-171 Rev 2 · §3.12.1

Periodically assess the security controls in organizational systems to determine if the controls are effective in their application.

Assessment objectives

From NIST SP 800-171A · 2 objectives must be met to satisfy this control
3.12.1[a] the frequency of security control assessments is defined.
Examine
[SELECT FROM: Security assessment and authorization policy; procedures addressing security assessment planning; procedures addressing security assessments; security assessment plan; security plan; other relevant documents or records].
Interview
[SELECT FROM: Personnel with security assessment responsibilities; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms supporting security assessment, security assessment plan development, and security assessment reporting].
3.12.1[b] security controls are assessed with the defined frequency to determine if the controls are effective in their application.
Examine
[SELECT FROM: Security assessment and authorization policy; procedures addressing security assessment planning; procedures addressing security assessments; security assessment plan; security plan; other relevant documents or records].
Interview
[SELECT FROM: Personnel with security assessment responsibilities; personnel with information security responsibilities].
Test
[SELECT FROM: Mechanisms supporting security assessment, security assessment plan development, and security assessment reporting].

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. 5-point control under the DoD Assessment Methodology. Highest scoring impact — treat as a foundational requirement. Not POA&M-eligible — must be implemented at assessment time.