sc-37-out-of-band-channels

name	SC-37_out-of-band-channels
description	Employ the following out-of-band channels for the physical delivery or electronic transmission of [organization-defined] to [organization-defined]: [o
category	configuration
version	5.2.0
author	cyberstrike-official
tags	["nist","sp800-53","rev5","sc-37","sc"]
tech_stack	["aws","azure","gcp","linux","windows","network"]
cwe_ids	["CWE-311"]
chains_with	["AC-2","CM-3","CM-5","CM-7","IA-2","IA-4","IA-5","MA-4","SC-12","SI-3"]
prerequisites	[]
severity_boost	{"AC-2":"Chain with AC-2 for comprehensive security coverage","CM-3":"Chain with CM-3 for comprehensive security coverage","CM-5":"Chain with CM-5 for comprehensive security coverage"}

SC-37 Out-of-band Channels

High-Level Description

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

Out-of-band channels include local, non-network accesses to systems; network paths physically separate from network paths used for operational traffic; or non-electronic paths, such as the U.S. Postal Service. The use of out-of-band channels is contrasted with the use of in-band channels (i.e., the same channels) that carry routine operational traffic. Out-of-band channels do not have the same vulnerability or exposure as in-band channels. Therefore, the confidentiality, integrity, or availability compromises of in-band channels will not compromise or adversely affect the out-of-band channels. Organizations may employ out-of-band channels in the delivery or transmission of organizational items, including authenticators and credentials; cryptographic key management information; system and data backups; configuration management changes for hardware, firmware, or software; security updates; maintenance information; and malicious code protection updates. For example, cryptographic keys for encrypted files are delivered using a different channel than the file.

What to Check

• Verify SC-37 Out-of-band Channels is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for SC-37

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-37 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
cloud-audit-mcp	Check encryption and network controls	cloud_audit_encryption
nmap	Network scanning	nmap -sV --script ssl-enum-ciphers

Remediation Guide