Media Access restricts who can get to the Controlled Unclassified Information (CUI) that lives on system media. Where Media Storage (03.08.01) physically controls and secures the media, Media Access (03.08.02) governs access to the CUI on it. It is a single statement: restrict access to CUI on system media to authorized personnel or roles. Per the NIST discussion, access can be restricted by physically controlling the media through inventories, check-out and return procedures, and accountability, and for digital media, access to CUI can be restricted using cryptographic means, with encryption at rest addressed in Transmission and Storage Confidentiality (03.13.08).
A common difficulty with this requirement is having secure storage but no real restriction on who can access the media. A shared media library that anyone can pull from, or an unencrypted external drive that any user can read, both fail this requirement. Access to the CUI on media has to be limited to the people or roles that are authorized for it.
Where things stand for companies facing the transition from NIST 800-171 R2 to R3:
The following is reproduced verbatim from NIST 800-171 R3, requirement 03.08.02 Media Access. Only the formatting has been adjusted for readability. This is a single statement with no lettered parts:
The source control is MP-02 from NIST 800-53. There are no Organization-Defined Parameters (ODPs). Per the NIST discussion, access to CUI on system media can be restricted by physically controlling the media, and for digital media it can be restricted by cryptographic means, with encryption of data at rest addressed in 03.13.08. You can read the requirement directly at NIST 800-171 R3, 03.08.02 (p. 45).
None (0). Requirement 03.08.02 contains no bracketed assignment, so there is no organization-defined value to select and nothing for the DoD to specify. The requirement applies as written.
Your System Security Plan (SSP) narrative for 03.08.02 therefore records how the requirement is implemented rather than a parameter you chose.
NIST 800-171A R3 breaks 03.08.02 into one (1) determination statement, and it has no Organization-Defined Parameters (ODPs). The AO is:
The single objective is that access to CUI on media is restricted to authorized personnel or roles. An assessor will look at both physical and cryptographic restrictions. The full guidance on assessment methods and objects, is in NIST 800-171A R3, 03.08.02 (p. 58).
Examine: physical protection policy and procedures; media protection policy and procedures; procedures for media access restrictions; access control policy and procedures; media storage facilities; access control records; system security plan.
Interview: personnel with system media protection responsibilities; personnel with information security responsibilities; system administrators.
Test: processes for restricting information on media; mechanisms for supporting or implementing media access restrictions.
03.08.02 maps from NIST 800-171 R2 requirement 3.8.2 (limit access to CUI on system media to authorized users):
Mapped against the one (1) AO, it is direct (minimal effort), with no net-new AOs and none with no mapping. This is a clean carry-forward. The concept and the source control (MP-02) are unchanged. R3 expresses the population as authorized personnel or roles rather than authorized users, which is a wording refinement rather than a substantive change. If you satisfied R2 3.8.2, you are satisfying 03.08.02.
Source Control in NIST 800-53 R5:
Secure Controls Framework (SCF) Crosswalk
Organizations running a single control set across multiple frameworks can satisfy 03.08.02 through the following SCF controls:
The crosswalks from NIST 800-171 R3 and NIST 800-171A R3 to the SCF are available at no cost through the SCF Set Theory Relationship Mapping (STRM): https://securecontrolsframework.com/start-here/set-theory-relationship-mapping-strm. The STRM also carries the relationship type for each mapping (Equal, Subset Of, Intersects With), which tells you whether an SCF control fully satisfies the requirement or only part of it. Mapping above taken from SCF 2026.3.
The following are issues teams may encounter rather than certainties. They are about actually restricting access, each of which needs documented evidence of due diligence and due care such as policies, standards, procedures, and configuration screenshots:
Reasonable objective evidence for an assessment is often subjective. The following examples of evidence to address NIST 800-171 R3 03.08.02 are sourced from the SCF Evidence Request List (ERL), available at https://securecontrolsframework.com/free-content/scf-download. These ERL artifacts are mapped to NIST 800-171 R3 03.08.02 through SCF controls. They establish a starting point for discussions on what an organization needs to have for evidence of due diligence and due care to withstand external scrutiny by an assessor or regulator.
Alongside these, keep the System Security Plan (SSP) narrative for 03.08.02.
With the single AO mapping directly, 03.08.02 is a light lift, especially where storage and encryption are already in place. A realistic sequence:
How many assessment objectives does NIST 800-171 R3 03.08.02 have? NIST 800-171A R3 breaks 03.08.02 into one (1) assessment objectives. An assessor works through each one separately, so each needs its own evidence.
Which NIST 800-53 R5 control does NIST 800-171 R3 03.08.02 come from? MP-02.
How many Organization-Defined Parameters (ODPs) does NIST 800-171 R3 03.08.02 have? None (0). The requirement contains no bracketed assignment, so there is no organization-defined value and nothing for the DoD to specify.
Where does NIST 800-171 R3 03.08.02 sit in the NIST 800-171 R3 Kill Chain? Phase 8, Segmented Network Architecture. The Kill Chain is a phased model for sequencing R3 implementation, and it assigns this requirement to that phase.
03.08.02 Media Access restricts access to CUI on system media to authorized personnel or roles. It maps directly from R2 3.8.2, so there is no net-new work. The recurring problem is securing the media without restricting who can access the CUI on it. Limit access to authorized personnel or roles using physical procedures and, for digital media, cryptographic controls.
Authoritative sources:
Authoritative sources:
This guide reproduces U.S. Government text from NIST 800-171 R3 and NIST 800-171A R3. It is educational, not legal or assessment advice. Last reviewed: 2026-09-22.
