sa-8-18-trusted-communications-channels

name	SA-8(18)_trusted-communications-channels
description	Implement the security design principle of trusted communications channels in [organization-defined].
category	configuration
version	5.2.0
author	cyberstrike-official
tags	["nist","sp800-53","rev5","sa-8-18","sa","enhancement"]
tech_stack	["any"]
cwe_ids	["CWE-16"]
chains_with	["SC-8","SC-12","SC-13"]
prerequisites	["SA-8"]
severity_boost	{"SC-8":"Chain with SC-8 for comprehensive security coverage","SC-12":"Chain with SC-12 for comprehensive security coverage","SC-13":"Chain with SC-13 for comprehensive security coverage"}

SA-8(18) Trusted Communications Channels

Enhancement of: SA-8

High-Level Description

Family: System and Services Acquisition (SA) Framework: NIST SP 800-53 Rev 5

The principle of trusted communication channels states that when composing a system where there is a potential threat to communications between components (i.e., the interconnections between components), each communication channel is trustworthy to a level commensurate with the security dependencies it supports (i.e., how much it is trusted by other components to perform its security functions). Trusted communication channels are achieved by a combination of restricting access to the communication channel (to ensure an acceptable match in the trustworthiness of the endpoints involved in the communication) and employing end-to-end protections for the data transmitted over the communication channel (to protect against interception and modification and to further increase the assurance of proper end-to-end communication).

What to Check

• Verify SA-8(18) Trusted Communications Channels is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SA-8(18)
• Verify enhancement builds upon base control SA-8

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SA-8(18) 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

Tool	Purpose	Usage
Manual Review	Documentation and interview-based	N/A

Remediation Guide

Control Statement

Implement the security design principle of trusted communications channels in [organization-defined].

Implementation Guidance