cyberstrikeus CM-7(4) Unauthorized Software — Deny-by-exception
Enhancement of: CM-7
High-Level Description
Family: Configuration Management (CM) Framework: NIST SP 800-53 Rev 5
Unauthorized software programs can be limited to specific versions or from a specific source. The concept of prohibiting the execution of unauthorized software may also be applied to user actions, system ports and protocols, IP addresses/ranges, websites, and MAC addresses.
What to Check
- Verify CM-7(4) Unauthorized Software — Deny-by-exception is documented in SSP
- Validate all 3 control requirements are implemented
- Confirm control is operating effectively
- Review evidence of continuous monitoring for CM-7(4)
- Verify enhancement builds upon base control CM-7
How to Test
Step 1: Review Documentation
Examine the System Security Plan (SSP) and related artifacts for CM-7(4) 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 configuration baselines | cloud_audit_config |
| AWS CLI | Review Config rules | aws configservice describe-config-rules |
Remediation Guide
Control Statement
Identify [organization-defined]; Employ an allow-all, deny-by-exception policy to prohibit the execution of unauthorized software programs on the system; and Review and update the list of unauthorized software programs [organization-defined].
Implementation Guidance
Unauthorized software programs can be limited to specific versions or from a specific source. The concept of prohibiting the execution of unauthorized software may also be applied to user actions, system ports and protocols, IP addresses/ranges, websites, and MAC addresses.
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| CM-7(4) Unauthorized Software — Deny-by-exception not implemented | Medium | Configuration Management |
| CM-7(4) partially implemented | Low | Incomplete Configuration Management |
CWE Categories
| CWE ID | Title |
|---|---|
| CWE-16 | Configuration |
References
- NIST SP 800-53 Rev 5 - CM-7(4)
- 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-6, CM-8, CM-10, PL-9, PM-5) reviewed