RHEL 8 must securely compare internal information system clocks at least every 24 hours with a server synchronized to an authoritative time source, such as the United States Naval Observatory (USNO) time servers, or a time server designated for the appropriate DoD network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS).

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230484	RHEL-08-030740	SV-230484r877038_rule		Medium

Description
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). If time stamps are not consistently applied and there is no common time reference, it is difficult to perform forensic analysis. Time stamps generated by the operating system include date and time. Time is commonly expressed in Coordinated Universal Time (UTC), a modern continuation of Greenwich Mean Time (GMT), or local time with an offset from UTC. RHEL 8 utilizes the "timedatectl" command to view the status of the "systemd-timesyncd.service". The "timedatectl" status will display the local time, UTC, and the offset from UTC. 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-000356-GPOS-00144, SRG-OS-000359-GPOS-00146

Description

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). If time stamps are not consistently applied and there is no common time reference, it is difficult to perform forensic analysis. Time stamps generated by the operating system include date and time. Time is commonly expressed in Coordinated Universal Time (UTC), a modern continuation of Greenwich Mean Time (GMT), or local time with an offset from UTC. RHEL 8 utilizes the "timedatectl" command to view the status of the "systemd-timesyncd.service". The "timedatectl" status will display the local time, UTC, and the offset from UTC. 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-000356-GPOS-00144, SRG-OS-000359-GPOS-00146

STIG	Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide	2023-09-11

Details

Check Text ( C-33153r568198_chk )
Verify RHEL 8 is securely comparing internal information system clocks at least every 24 hours with an NTP server with the following commands: $ sudo grep maxpoll /etc/chrony.conf server 0.us.pool.ntp.mil iburst maxpoll 16 If the "maxpoll" option is set to a number greater than 16 or the line is commented out, this is a finding. Verify the "chrony.conf" file is configured to an authoritative DoD time source by running the following command: $ sudo grep -i server /etc/chrony.conf server 0.us.pool.ntp.mil If the parameter "server" is not set or is not set to an authoritative DoD time source, this is a finding.

Check Text ( C-33153r568198_chk )

Verify RHEL 8 is securely comparing internal information system clocks at least every 24 hours with an NTP server with the following commands:

$ sudo grep maxpoll /etc/chrony.conf

server 0.us.pool.ntp.mil iburst maxpoll 16

If the "maxpoll" option is set to a number greater than 16 or the line is commented out, this is a finding.

Verify the "chrony.conf" file is configured to an authoritative DoD time source by running the following command:

$ sudo grep -i server /etc/chrony.conf
server 0.us.pool.ntp.mil

If the parameter "server" is not set or is not set to an authoritative DoD time source, this is a finding.

Fix Text (F-33128r568199_fix)
Configure the operating system to securely compare internal information system clocks at least every 24 hours with an NTP server by adding/modifying the following line in the /etc/chrony.conf file. server [ntp.server.name] iburst maxpoll 16