SI-4(22)_unauthorized-network-services

SI-4(22) Unauthorized Network Services

Enhancement of: SI-4

High-Level Description

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

Unauthorized or unapproved network services include services in service-oriented architectures that lack organizational verification or validation and may therefore be unreliable or serve as malicious rogues for valid services.

What to Check

• Verify SI-4(22) Unauthorized Network Services is documented in SSP
• Validate all 2 control requirements are implemented
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SI-4(22)
• 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(22) 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

Detect network services that have not been authorized or approved by [organization-defined] ; and [organization-defined] when detected.

Implementation Guidance

Unauthorized or unapproved network services include services in service-oriented architectures that lack organizational verification or validation and may therefore be unreliable or serve as malicious rogues for valid services.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SI-4(22)
• 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 (CM-7) reviewed