AC-4(13)_decomposition-into-policy-relevant-subcomponents

AC-4(13) Decomposition into Policy-relevant Subcomponents

Enhancement of: AC-4

High-Level Description

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

Decomposing information into policy-relevant subcomponents prior to information transfer facilitates policy decisions on source, destination, certificates, classification, attachments, and other security- or privacy-related component differentiators. Policy enforcement mechanisms apply filtering, inspection, and/or sanitization rules to the policy-relevant subcomponents of information to facilitate flow enforcement prior to transferring such information to different security domains.

What to Check

• Verify AC-4(13) Decomposition into Policy-relevant Subcomponents is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for AC-4(13)
• Verify enhancement builds upon base control AC-4

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for AC-4(13) 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

When transferring information between different security domains, decompose information into [organization-defined] for submission to policy enforcement mechanisms.

Implementation Guidance

Decomposing information into policy-relevant subcomponents prior to information transfer facilitates policy decisions on source, destination, certificates, classification, attachments, and other security- or privacy-related component differentiators. Policy enforcement mechanisms apply filtering, inspection, and/or sanitization rules to the policy-relevant subcomponents of information to facilitate flow enforcement prior to transferring such information to different security domains.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - AC-4(13)
• 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 (none) reviewed