V-275613

Discussion

Inaccurate time stamps make it more difficult to correlate events and can lead to an inaccurate analysis. Determining the correct time a particular event occurred on a system is critical when conducting forensic analysis and investigating system events. Sources outside the configured acceptable allowance (drift) may be inaccurate. Synchronizing internal information system clocks provides uniformity of time stamps for information systems with multiple system clocks and systems connected over a network. Organizations should consider endpoints that may not have regular access to the authoritative time server (e.g., mobile, teleworking, and tactical endpoints). Note that USNO offers authenticated NTP service to DOD and U.S. Government agencies operating on the NIPR and SIPR networks. Visit https://www.usno.navy.mil/USNO/time/ntp/DOD-customers for more information. Satisfies: SRG-OS-000355-GPOS-00143, SRG-OS-000785-GPOS-00250

Check Content

Verify Ubuntu OS is configured to compare the system clock at least every 24 hours to the authoritative time source by using the following command: 
 
Note: If the system is not networked, this requirement is not applicable. 
 
     $ sudo grep maxpoll -ir /etc/chrony* 
     server tick.usno.navy.mil iburst maxpoll 16 
  
If the "maxpoll" option is set to a number greater than 16, the line is commented out, or is missing, this is a finding. 
  
Verify that the "chrony.conf" file is configured to an authoritative DOD time source by using the following command:  
  
     $ sudo grep -ir server /etc/chrony* 
     server tick.usno.navy.mil iburst maxpoll 16 
     server tock.usno.navy.mil iburst maxpoll 16 
     server ntp2.usno.navy.mil iburst maxpoll 16 
  
If "server" is not defined, is not set to an authoritative DOD time source, is commented out, or missing, this is a finding.