SC-25 Thin Nodes
High-Level Description
Family: System and Communications Protection (SC) Framework: NIST SP 800-53 Rev 5
The deployment of system components with minimal functionality reduces the need to secure every endpoint and may reduce the exposure of information, systems, and services to attacks. Reduced or minimal functionality includes diskless nodes and thin client technologies.
What to Check
- Verify SC-25 Thin Nodes is documented in SSP
- Confirm control is operating effectively
- Review evidence of continuous monitoring for SC-25
How to Test
Step 1: Review Documentation
Examine the System Security Plan (SSP) and related artifacts for SC-25 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
Control Statement
Employ minimal functionality and information storage on the following system components: [organization-defined].
Implementation Guidance
The deployment of system components with minimal functionality reduces the need to secure every endpoint and may reduce the exposure of information, systems, and services to attacks. Reduced or minimal functionality includes diskless nodes and thin client technologies.
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| SC-25 Thin Nodes not implemented | High | System and Communications Protection |
| SC-25 partially implemented | Medium | Incomplete System and Communications Protection |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-311 | Missing Encryption of Sensitive Data |
References
- NIST SP 800-53 Rev 5 - SC-25
- 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 (SC-30, SC-44) reviewed