NIST SP 800-171 Rev 2 · 3.5 Identification & Authentication

3.5.8 Prohibit password reuse

Prohibit password reuse for a specified number of generations.

SPRS weight: 1; 1 point deducted from 110 when not implemented.
CMMC level: L2; Level 2 only; not among the 17 Level 1 practices.
Assessment objectives: 2; From NIST SP 800-171A, each one a “determine if” an assessor answers.

What an assessor checks

NIST SP 800-171A breaks 3.5.8 into 2 objectives. Every one has to be met for the requirement to be met; a partial answer scores as not implemented.

[a]Determine if the number of generations during which a password cannot be reused is specified.
[b]Determine if reuse of passwords is prohibited during the specified number of generations.

Examine: [SELECT FROM: Identification and authentication policy; password policy; procedures addressing authenticator management; security plan; system design documentation; system configuration settings and associated documentation; password configurations and associated documentation; other relevant documents or records].
Interview: [SELECT FROM: Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators; system developers].
Test: [SELECT FROM: Mechanisms supporting or implementing password-based authenticator management capability].

May be carried on a Level 2 POA&M · 1 point deducted

A 1-point requirement outside the six named exclusions - eligible to carry, and NOT MET until a closeout assessment confirms it.

A POA&M is only permitted at a score of 88 or above, and closes in one 180-day window. Check a full gap list or compute your score.

No direct mapping.

This page and the MacTech CMMC MCP server render the same dataset. Ask your assistant and it will answer from the methodology, not from memory.

lookup_control 3.5.8
get_assessment_objectives 3.5.8
generate_poam_entries ["3.5.8"]

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