Mapped to NIST 800-171 Requirement: 3.13.14
CMMC Assessment Objective: SC.L2-3.13.14[c]
What This Control Means
This is the real-world operational validation checkpoint.
You must demonstrate that:
• Your firewalls, DLP systems, proxies, CASBs, and encryption tools are deployed and working
• Controls actively monitor, block, or restrict CUI transfers at boundaries
• Tools and configurations match your documented strategies
• Unauthorized communications are detected, blocked, or logged
In other words: your CUI transfer protections are alive and doing their job.
Why It Matters
If protections are documented but inactive:
• CUI can easily leak across unsecured channels
• Attackers can infiltrate via unmonitored connections
• Compliance with NIST 800-171 and CMMC requirements collapses
• You lose control over sensitive data without even realizing it
Controls only count if they are enforced and operational.
How to Implement It
1. Validate Controls on Boundary Systems
• Firewalls:
◦ Confirm outbound/inbound rules restrict unauthorized CUI transfers
◦ Check for specific controls tied to CUI traffic (e.g., port/protocol restrictions)
• DLP:
◦ Ensure policies are active on email servers, file shares, cloud platforms
• CASB:
◦ Enforce encryption and access control for cloud data handling CUI
2. Monitor Traffic and Transfer Logs
• Review:
◦ Firewall and DLP logs for blocked or flagged transfers
◦ SIEM alerts tied to outbound CUI data flows
◦ VPN session logs showing protected channels only
3. Conduct Tests
• Simulate unauthorized outbound CUI attempts:
◦ Try to send unencrypted sensitive data externally
◦ Attempt uploading CUI to unapproved cloud services
• Confirm alerts, blocks, or policy enforcement occurs
4. Audit Administrative Controls
• Ensure unauthorized personnel cannot alter or disable CUI protection settings
Evidence the Assessor Will Look For
• Firewall rule sets showing restrictions on CUI transfers
• DLP reports showing detected or blocked CUI incidents
• Proxy and CASB enforcement logs
• Incident reports or alerts triggered by CUI transfer attempts
• Screenshots or reports from cloud platforms showing restricted upload/download controls
Common Gaps
• Policies exist but no active DLP enforcement or monitoring
• No outbound traffic filtering focused on CUI protection
• Unsecured cloud services (Dropbox, Google Drive) accessible without restriction
• Security controls installed but not tuned or actively used for CUI-specific scenarios
How Cuick Trac Helps
Cuick Trac supports this requirement by:
• Monitoring live enforcement of CUI communication and transfer restrictions
• Tracking firewall, DLP, and proxy rule enforcement at system boundaries
• Logging alerts and incidents tied to outbound/inbound CUI traffic
• Generating reports linking operational protections to your SSP and risk register
• Alerting on misconfigurations, missing protections, or failed control enforcement
With Cuick Trac, your CUI flow protections are active, verified, and audit-ready every day.
Final CTA
Documented defenses are good—operational defenses are essential.
Schedule a Cuick Trac demo to ensure your CUI communications are controlled, monitored, and enforced at every boundary.