SC-3(5)_layered-structures

SC-3(5) Layered Structures

Enhancement of: SC-3

High-Level Description

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

The implementation of layered structures with minimized interactions among security functions and non-looping layers (i.e., lower-layer functions do not depend on higher-layer functions) enables the isolation of security functions and the management of complexity.

What to Check

• Verify SC-3(5) Layered Structures is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SC-3(5)
• Verify enhancement builds upon base control SC-3

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-3(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

Implement security functions as a layered structure minimizing interactions between layers of the design and avoiding any dependence by lower layers on the functionality or correctness of higher layers.

Implementation Guidance

The implementation of layered structures with minimized interactions among security functions and non-looping layers (i.e., lower-layer functions do not depend on higher-layer functions) enables the isolation of security functions and the management of complexity.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SC-3(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 (none) reviewed