AC-5_separation-of-duties

AC-5 Separation of Duties

High-Level Description

Family: Access Control (AC) Framework: NIST SP 800-53 Rev 5

Separation of duties addresses the potential for abuse of authorized privileges and helps to reduce the risk of malevolent activity without collusion. Separation of duties includes dividing mission or business functions and support functions among different individuals or roles, conducting system support functions with different individuals, and ensuring that security 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 systems and system components when developing policy on separation of duties. Separation of duties is enforced through the account management activities in AC-2 , access control mechanisms in AC-3 , and identity management activities in IA-2, IA-4 , and IA-12.

What to Check

• Verify AC-5 Separation of Duties is documented in SSP
• Validate all 2 control requirements are implemented
• Confirm control is operating effectively
• Review evidence of continuous monitoring for AC-5

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for AC-5 implementation details. Verify the organization has documented how this control is satisfied.

Step 2: Validate Implementation

# For cloud environments, use cloud-audit-mcp tools
# For on-premises, review system configurations directly

# Example: Check if account management policies exist
grep -r "account.management\|access.control" /etc/security/ 2>/dev/null

Step 3: Test Operating Effectiveness

Verify the control is actively functioning, not just documented. Check logs, configurations, and operational evidence.

Tools

Remediation Guide

Control Statement

Identify and document [organization-defined] ; and Define system access authorizations to support separation of duties.

Implementation Guidance

Separation of duties addresses the potential for abuse of authorized privileges and helps to reduce the risk of malevolent activity without collusion. Separation of duties includes dividing mission or business functions and support functions among different individuals or roles, conducting system support functions with different individuals, and ensuring that security 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 systems and system components when developing policy on separation of duties. Separation of duties is enforced through the account management activities in AC-2 , access control mechanisms in AC-3 , and identity management activities in IA-2, IA-4 , and IA-12.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - AC-5
• NIST SP 800-53A Rev 5 (Assessment Procedures)
• NIST SP 800-53 Rev 5 Full Catalog

Checklist

• Control documented in SSP
• Implementation evidence collected
• Operating effectiveness validated
• Continuous monitoring in place
• Related controls (AC-2, AC-3, AC-6, AU-9, CM-5) reviewed