The F5 BIG-IP appliance must authenticate Network Time Protocol (NTP) sources using authentication that is cryptographically based.
An XCCDF Rule
Description
<VulnDiscussion>If NTP 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.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-266086r1024925_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
From the BIG-IP console, type the following commands:
echo "1 M <passphrase> #MD5 Key" > /etc/ntp/keys
Note: This command assumes that no other keys have been previously configured in the /etc/ntp/keys file. Running this command will overwrite the file.