V-217339

Discussion

If Network Time Protocol is not authenticated, an attacker can introduce a rogue NTP server. This rogue server can then be used to send incorrect time information to network devices, which will make log timestamps inaccurate and affect scheduled actions. NTP authentication is used to prevent this tampering by authenticating the time source.

Check Content

Review the router configuration to verify that it is compliant with this requirement as shown in the configuration example below.

system {
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…
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    }
    ntp {
        authentication-key 1 type md5 value "$8$LMK7NbHkPTQnVwF/"; ## SECRET-DATA
        authentication-key 2 type md5 value "$8$I3KceWbwgJUH"; ## SECRET-DATA
        server x.x.x.x key 1 prefer; ## SECRET-DATA
        server x.x.x.x key 2; ## SECRET-DATA
        trusted-key [1 2];
    }

If the router is not configured to authenticate NTP sources using authentication that is cryptographically based, this is a finding.