3.13.15Protect session authenticity in Rev. 3
No significant change: 03.13.15 Session Authenticity.
Status as of 2026-09-08
Rev. 2 is what a contract requires today. DFARS 252.204-7012 and the CMMC rule at 32 CFR 170 point at NIST SP 800-171 Rev. 2, and a standing DoD class deviation keeps it there. NIST has published Rev. 3, but publishing a revision does not change an obligation. A move to Rev. 3 would arrive through the Department's reform process and formal rulemaking, a change to that deviation or an amendment to the rule, not through publication. The Department has published its organization-defined parameter values for Rev. 3 in preparation; that is groundwork, not adoption.
Side by side
Rev. 2 · in force 3.13.15 Communications Authenticity
Assessment objectives · 800-171A
- [a] the authenticity of communications sessions is protected
Rev. 3 · not adopted 03.13.15 Session Authenticity
Protect the authenticity of communications sessions.
Determination statements · 800-171A Rev. 3
- 03.13.15 the authenticity of communications sessions is protected.
Draws on Rev. 2 3.13.15.
Left: NIST SP 800-171 Rev. 2 and 800-171A, verbatim. Right: NIST SP 800-171 Rev. 3 and 800-171A Rev. 3, verbatim, with organization-defined blanks highlighted.
Word by word
The Rev. 2 requirement compared with its Rev. 3 successor. A mechanical comparison of the two verbatim texts, not an interpretation.
removed in Rev. 3 added in Rev. 3
Rev. 2 3.13.15 → Rev. 3 03.13.15 Session Authenticity
6 words kept, 0 removed, 0 added. Rev. 3 statement labels omitted for the comparison.
What NIST says changed
- New security requirement title
NIST, SP 800-171 Rev. 2 to Rev. 3 change analysis, class “No significant change”. At adoption, Bedrock files this under “Carries as-is”.
NIST's Rev. 3 discussion for 03.13.15
Protecting session authenticity addresses communications protection at the session level, not at the packet level. Such protection establishes grounds for confidence at both ends of the communications sessions in the ongoing identities of other parties and the validity of the transmitted information. Authenticity protection includes protecting against adversary-in-the-middle attacks, session hijacking, and the insertion of false information into sessions.
What this means for you now
Nothing changes in what you are assessed against until a class deviation or a published rule adopts Rev. 3. Keep meeting 3.13.15 as written in Rev. 2.
Bedrock CMMC shows this same comparison against your own package, with your current status on the Rev. 2 side, so the day adoption lands the migration is a review, not a rewrite.
Where this page's facts come from
- Rev. 2 text and objectives
- bedrock-cmmc-api@89b8e8e:migrations/004_reference_requirements.sql#Requirement.basicRequirement@rev2; bedrock-cmmc-api@89b8e8e:migrations/005_reference_objectives.sql#AssessmentObjective.description@rev2
- Mapping and change class
- bedrock-cmmc-api@89b8e8e:docs/reference/nist-800-171-rev3/normalized/r2_r3_transition_map.json#r2_to_r3
- Rev. 3 03.13.15
- bedrock-cmmc-api@89b8e8e:docs/reference/nist-800-171-rev3/normalized/rev3.json#requirements[]