Mapped to NIST 800-171 Requirement: 3.5.3
CMMC Assessment Objective: IA.L2-3.5.3[c]
What This Objective Means
Replay-resistant authentication is designed to prevent attackers from intercepting and reusing authentication credentials (like passwords, tokens, or session IDs) to gain unauthorized access.
This control requires that your systems are configured to use authentication protocols and mechanisms that mitigate those risks.
Accepted methods include:
• One-time passwords (OTPs)
• Time-based tokens
• Mutual TLS
• Challenge-response authentication
• Kerberos
• SSH with key-based login
• Secure API token exchange with rotation
Why It Matters
If your authentication system lacks replay resistance:
• Credentials can be captured and reused
• Session hijacking becomes easier
• Remote access becomes a critical vulnerability
• Systems become non-compliant with CUI protection standards
Simply requiring secure authentication is not enough—it must be correctly configured at the system level.
How to Implement It
1. Enforce Secure Protocols
• Use TLS/SSL for all authentication traffic (e.g., HTTPS, SSH, LDAPS)
• Block legacy protocols like Telnet, HTTP, or FTP
2. Configure Authentication Methods with Replay Resistance
• Windows: Use Kerberos or NTLMv2 with session integrity
• Linux: Use PAM with OTPs, SSH key-pairs, or MFA integration
3. Apply Replay Resistance in Cloud/Remote Access
• Enforce MFA with rotating tokens for VPN and SaaS
• Require token expiration, revalidation, or session binding
4. Implement API-Level Protection
• Use short-lived access tokens with refresh logic
• Apply rate-limiting, IP filtering, and non-reusable authentication tokens
5. Audit Configuration Regularly
• Review system settings and test authentication flows
• Look for any services still accepting static credentials or weak protocols
Evidence the Assessor Will Look For
• System configuration exports showing replay-resistant authentication is enabled
• Screenshots or dashboards from MFA or identity providers
• API configuration examples showing token expiration and renewal
• Protocol enforcement settings (e.g., TLS versions, SSH configurations)
• Logs showing successful authentication via secure, non-replayable methods
Common Gaps
• Secure authentication protocols are supported but not enforced
• API services use static tokens or long-lived keys without rotation
• SSH or RDP sessions are accessible without replay protection (e.g., reused credentials)
• No documentation or logs to prove replay resistance
How Cuick Trac Helps
Cuick Trac supports this control by:
• Enforcing replay-resistant authentication across all enclave access points
• Blocking legacy or insecure authentication protocols by default
• Using identity providers that support time-based token validation and mutual TLS
• Automatically validating system configurations against compliance standards
• Providing pre-configured, secure authentication templates for Windows, Linux, and cloud platforms
With Cuick Trac, replay resistance isn’t just enabled—it’s built into the fabric of the system.
Final CTA
Replay protection doesn’t happen by accident—it happens through configuration.
Schedule a Cuick Trac demo to verify your authentication controls are secure, enforced, and audit-ready.