CMMC readiness · NIST 800-171 alignment · DFARS support Mon–Fri · 0800–1800 ET
Controls / Identification and Authentication / 3.5.2
3.5.2
IA.L1-3.5.2 · Level 1 + 2

Authenticate (or verify) the identities of users, processes, or devices, as a prerequisite to…

NIST SP 800-171 Rev 2 · §3.5.2

Authenticate (or verify) the identities of users, processes, or devices, as a prerequisite to allowing access to organizational systems

Assessment objectives

From NIST SP 800-171A · 3 objectives must be met to satisfy this control
3.5.2[a] the identity of each user is authenticated or verified as a prerequisite to system access.
Examine
[SELECT FROM: Identification and authentication policy; procedures addressing authenticator management; security plan; system design documentation; system configuration settings and associated documentation; list of system authenticator types; change control records associated with managing system authenticators; system audit logs and records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators].
Test
[SELECT FROM: Mechanisms supporting or implementing authenticator management capability].
3.5.2[b] the identity of each process acting on behalf of a user is authenticated or verified as a prerequisite to system access.
Examine
[SELECT FROM: Identification and authentication policy; procedures addressing authenticator management; security plan; system design documentation; system configuration settings and associated documentation; list of system authenticator types; change control records associated with managing system authenticators; system audit logs and records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators].
Test
[SELECT FROM: Mechanisms supporting or implementing authenticator management capability].
3.5.2[c] the identity of each device accessing or connecting to the system is authenticated or verified as a prerequisite to system access.
Examine
[SELECT FROM: Identification and authentication policy; procedures addressing authenticator management; security plan; system design documentation; system configuration settings and associated documentation; list of system authenticator types; change control records associated with managing system authenticators; system audit logs and records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators].
Test
[SELECT FROM: Mechanisms supporting or implementing authenticator management capability].

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.