Password Reuse
Prohibit password reuse for a specified number of generations.
What gets scored, the objectives
IA.L2-3.5.8 is met only when every one of these 2 objectives, from NIST SP 800-171A, is satisfied. A single missed objective makes the whole requirement not met.
- a.the number of generations during which a password cannot be reused is specified
- b.reuse of passwords is prohibited during the specified number of generations
How this is assessed
NIST SP 800-171A defines three assessment methods. For IA.L2-3.5.8, whoever assesses it, including your own team in a self assessment, uses these:
Identification and authentication policy; password policy; procedures addressing authenticator management; system security plan; system design documentation; system configuration settings and associated documentation; password configurations and associated documentation; other relevant documents or records
Personnel with authenticator management responsibilities; personnel with information security responsibilities; system or network administrators; system developers
Mechanisms supporting or implementing password-based authenticator management capability
What it means, in context
Password lifetime restrictions do not apply to temporary passwords.
Individuals may not reuse their passwords for a defined period of time and a set number of passwords generated. Example You explain in your company ’s security policy tha t changing passwords regularly provides increased security by reducing the ability of adversaries to exploit stolen or purchased passwords over an extended period. You define how often individuals can reuse their passwords and the minimum number of password generations before reuse [a]. If a user tries to reuse a password before the number of password generations has been exceeded, an error message is generated, and the user is required to enter a new password [b].
What passing evidence looks like
The password history setting (reuse prohibited for the defined number of generations) from the enforcing system.
Common ways contractors fail IA.L2-3.5.8
- !Pure cloud Entra accounts handle history internally; for hybrid or local accounts show the enforced history number. State the generations count in policy either way.
The step by step walkthrough for Microsoft 365 GCC High, Google Workspace, and on premises setups, plus the exact evidence to capture, lives inside the CMMC Level 2 plan.
Prove IA.L2-3.5.8, and the other 109
The Level 2 workspace walks your team through all 110 requirements at the objective level, drafts your SSP section by section from your own record for your team to read and accept, gives a prime or your own internal auditor a read only seat on the same record, and a credentialed officer reviews every step.
Book a free advisory callNo credit card, and Level 1 and Level 2 are both open, so sign up for the level your contracts call for. Self assessed and self attested: you score yourself in SPRS on a three year cycle and your senior official affirms it every year. As of September 3, 2026 a class deviation directs contracting officers to remove third party assessment from contracts. The program rule still provides for it, so your solicitation sets the track. Your team builds the same evidence either way. DFARS 252.204-7012 is unaffected, and the NIST SP 800-171 Rev 2 baseline is unchanged.
IA.L2-3.5.8 questions, answered
How many points is CMMC requirement IA.L2-3.5.8 worth?+
IA.L2-3.5.8 is worth 1 point in the CMMC Level 2 score under 32 CFR 170.24. If it is not met, you lose 1 from your total of 110.
Can IA.L2-3.5.8 be placed on a POA&M?+
Yes. A gap on IA.L2-3.5.8 can be deferred to a Plan of Action and Milestones, provided your overall score is 88 or better and the item closes within 180 days.
What family does IA.L2-3.5.8 belong to?+
IA.L2-3.5.8 is in the Identification & Authentication (IA) family, one of the 14 families of NIST SP 800-171 that make up CMMC Level 2.
- NIST SP 800-171 Rev. 2 3.5.8