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NIST SP 800-171 CUI Protection Center

03.01.04 — Separation of Duties

Read the official CUI requirement and assessment content, then use the separately labeled Bare Metal Cyber perspective to connect it to implementation, evidence, and sustained operation.

1Source controls
2Assessment objectives
3Assessment methods

03.01 — Access Control · NIST SP 800-171 Revision 3

Active
Official NIST requirement content

Security requirement

  1. a.Identify the duties of individuals requiring separation.
  2. b.Define system access authorizations to support separation of duties.
Official NIST discussion

Discussion

Separation of duties addresses the potential for abuse of authorized privileges and reduces the risk of malevolent activity without collusion. Separation of duties includes dividing mission functions and support functions among different individuals or roles, conducting system support functions with different individuals or roles (e.g., quality assurance, configuration management, network security, system management, assessments, and programming), and ensuring that personnel who administer access control functions do not also administer audit functions. Because separation of duty violations can span systems and application domains, organizations consider the entirety of their systems and system components when developing policies on separation of duties. This requirement is enforced by 03.01.02.

Bare Metal Cyber interpretation

Implementation perspective

Treat Separation of Duties as a CUI protection outcome that must be reflected in the system boundary, documented implementation, operational behavior, and assessment evidence. Pay particular attention to approved identities, least privilege, remote access, information flow, and the full account lifecycle.

  1. Confirm the requirement is in scope for the CUI system components, services, users, and external connections being assessed.
  2. Resolve every organization-defined parameter through an approved governance and tailoring process.
  3. Map each clause of the requirement to an accountable owner, implementation mechanism, and evidence source.
  4. Verify that inherited and shared implementations are supported by current provider evidence and responsibility boundaries.
  5. Collect evidence during normal operation and review changes, exceptions, and deficiencies on a risk-based cadence.

Questions to ask

  • Which CUI assets, data flows, users, and services are protected by this requirement?
  • Which portions are implemented locally, inherited, shared, or not applicable, and what evidence supports that determination?
  • Do the system security plan, deployed configuration, operating process, and assessment evidence tell the same story?
  • What change, incident, or threshold should trigger reassessment?

Evidence and validation

  • access authorization and approval records
  • account inventories and entitlement exports
  • access review results
  • authentication and authorization logs

Common failure patterns

  • CUI access that exceeds mission need
  • shared or orphaned accounts
  • remote access paths outside the approved boundary
  • access reviews that cannot be reconciled to deployed permissions
Official NIST SP 800-171A content

Assessment objectives and methods

Assessment objectives (2)
  1. a.

    duties of individuals requiring separation are identified.

  2. b.

    system access authorizations to support separation of duties are defined.

Examine

  • access control policy and procedures
  • procedures for the separation of duties and the division of responsibilities
  • system configuration settings
  • system audit records
  • system access authorizations
  • list of divisions of responsibility and separation of duties
  • system security plan
  • other relevant documents or records

Interview

  • personnel with responsibilities for defining the separation of duties and the division of responsibilities
  • personnel with information security responsibilities
  • system administrators

Test

  • mechanisms for implementing the separation of duties policy
Official source-control relationships

Source NIST SP 800-53 controls

These controls are referenced by the official SP 800-171 Rev. 3 OSCAL record. Open the corresponding control pages for complete control text, enhancements, D3FEND mappings, and related learning.

Source controlAC-5Open SP 800-53 control →
Source record

Authoritative sources

Bare Metal Cyber is an independent educational publisher and is not affiliated with or endorsed by NIST. The official publications, the responsible federal agency, and the governing contract or agreement determine applicability, tailoring, assessment depth, and required implementation.