SC-7(3) Access Points
Enhancement of: SC-7
High-Level Description
Family: System and Communications Protection (SC) Framework: NIST SP 800-53 Rev 5
Limiting the number of external network connections facilitates monitoring of inbound and outbound communications traffic. The Trusted Internet Connection DHS TIC initiative is an example of a federal guideline that requires limits on the number of external network connections. Limiting the number of external network connections to the system is important during transition periods from older to newer technologies (e.g., transitioning from IPv4 to IPv6 network protocols). Such transitions may require implementing the older and newer technologies simultaneously during the transition period and thus increase the number of access points to the system.
What to Check
- Verify SC-7(3) Access Points is documented in SSP
- Confirm control is operating effectively
- Review evidence of continuous monitoring for SC-7(3)
- 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(3) 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
Limit the number of external network connections to the system.
Implementation Guidance
Limiting the number of external network connections facilitates monitoring of inbound and outbound communications traffic. The Trusted Internet Connection DHS TIC initiative is an example of a federal guideline that requires limits on the number of external network connections. Limiting the number of external network connections to the system is important during transition periods from older to newer technologies (e.g., transitioning from IPv4 to IPv6 network protocols). Such transitions may require implementing the older and newer technologies simultaneously during the transition period and thus increase the number of access points to the system.
Risk Assessment
| Finding | Severity | Impact |
|---|---|---|
| SC-7(3) Access Points not implemented | High | System and Communications Protection |
| SC-7(3) 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-7(3)
- 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