SI-4(10)_visibility-of-encrypted-communications

SI-4(10) Visibility of Encrypted Communications

Enhancement of: SI-4

High-Level Description

Family: System and Information Integrity (SI) Framework: NIST SP 800-53 Rev 5

Organizations balance the need to encrypt communications traffic to protect data confidentiality with the need to maintain visibility into such traffic from a monitoring perspective. Organizations determine whether the visibility requirement applies to internal encrypted traffic, encrypted traffic intended for external destinations, or a subset of the traffic types.

What to Check

• Verify SI-4(10) Visibility of Encrypted Communications is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SI-4(10)
• Verify enhancement builds upon base control SI-4

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SI-4(10) 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

Make provisions so that [organization-defined] is visible to [organization-defined].

Implementation Guidance

Organizations balance the need to encrypt communications traffic to protect data confidentiality with the need to maintain visibility into such traffic from a monitoring perspective. Organizations determine whether the visibility requirement applies to internal encrypted traffic, encrypted traffic intended for external destinations, or a subset of the traffic types.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SI-4(10)
• 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