SC-7(19)_block-communication-from-non-organizationally-configured-hos

SC-7(19) Block Communication from Non-organizationally Configured Hosts

Enhancement of: SC-7

High-Level Description

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

Communication clients independently configured by end users and external service providers include instant messaging clients and video conferencing software and applications. Traffic blocking does not apply to communication clients that are configured by organizations to perform authorized functions.

What to Check

• Verify SC-7(19) Block Communication from Non-organizationally Configured Hosts is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SC-7(19)
• Verify enhancement builds upon base control SC-7

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-7(19) 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

Block inbound and outbound communications traffic between [organization-defined] that are independently configured by end users and external service providers.

Implementation Guidance

Communication clients independently configured by end users and external service providers include instant messaging clients and video conferencing software and applications. Traffic blocking does not apply to communication clients that are configured by organizations to perform authorized functions.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - SC-7(19)
• 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