Title

The system clock must be synchronized continuously, or at least daily. (Cat II impact)

Discussion

A synchronized system clock is critical for the enforcement of time-based policies and the correlation of logs and audit records with other systems. Internal system clocks tend to drift and require periodic resynchronization to ensure their accuracy. Software, such as ntpd, can be used to continuously synchronize the system clock with authoritative sources. Alternatively, the system may be synchronized periodically, with a maximum of one day between synchronizations. If the system is completely isolated (that is, it has no connections to networks or other systems), time synchronization is not required as no correlation of events or operation of time-dependent protocols between systems will be necessary. If the system is completely isolated, this requirement is not applicable.

Check Content

Check the system's configuration to determine if the NTP daemon is running continuously, or if a scheduled job is configured to synchronize time at least every hour. If the NTP daemon is not running, and there is no scheduled job for time synchronization, this is a finding.

Fix Text

Configure the system to synchronize time continuously or schedule a job to perform time synchronization at least once per hour. Consult system documentation for implementation details.

Additional Identifiers

Rule ID: SV-32521r1_rule

Vulnerability ID: V-22290

Group Title: GEN000241

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.