SC-46_cross-domain-policy-enforcement

SC-46 Cross Domain Policy Enforcement

High-Level Description

Family: System and Communications Protection (SC) Framework: NIST SP 800-53 Rev 5

For logical policy enforcement mechanisms, organizations avoid creating a logical path between interfaces to prevent the ability to bypass the policy enforcement mechanism. For physical policy enforcement mechanisms, the robustness of physical isolation afforded by the physical implementation of policy enforcement to preclude the presence of logical covert channels penetrating the security domain may be needed. Contact ncdsmo@nsa.gov for more information.

What to Check

• Verify SC-46 Cross Domain Policy Enforcement is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SC-46

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-46 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

Implement a policy enforcement mechanism [organization-defined] between the physical and/or network interfaces for the connecting security domains.

Implementation Guidance

For logical policy enforcement mechanisms, organizations avoid creating a logical path between interfaces to prevent the ability to bypass the policy enforcement mechanism. For physical policy enforcement mechanisms, the robustness of physical isolation afforded by the physical implementation of policy enforcement to preclude the presence of logical covert channels penetrating the security domain may be needed. Contact ncdsmo@nsa.gov for more information.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SC-46
• 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-4, SC-7) reviewed