V-202055

Discussion

A replay attack may enable an unauthorized user to gain access to the application. Authentication sessions between the authenticator and the application validating the user credentials must not be vulnerable to a replay attack. An authentication process resists replay attacks if it is impractical to achieve a successful authentication by recording and replaying a previous authentication message. Techniques used to address this include protocols using nonces (e.g., numbers generated for a specific one-time use) or challenges (e.g., TLS, WS_Security). Additional techniques include time-synchronous or challenge-response one-time authenticators.

Check Content

Determine if the network device implements replay-resistant authentication mechanisms for network access to privileged accounts. This requirement may be verified by demonstration, configuration review, or validated test results. This requirement may be met through use of a properly configured authentication server if the device is configured to use the authentication server. If the network device does not implement replay-resistant authentication mechanisms for network access to privileged accounts, this is a finding.