Title

RHEL 8 must prevent users from disabling session control mechanisms. (Cat III impact)

Discussion

A session lock is a temporary action taken when a user stops work and moves away from the immediate physical vicinity of the information system but does not want to log out because of the temporary nature of the absence. The session lock is implemented at the point where session activity can be determined. Rather than be forced to wait for a period of time to expire before the user session can be locked, RHEL 8 needs to provide users with the ability to manually invoke a session lock so users can secure their session if it is necessary to temporarily vacate the immediate physical vicinity. Tmux is a terminal multiplexer that enables a number of terminals to be created, accessed, and controlled from a single screen. Red Hat endorses tmux as the recommended session controlling package. Satisfies: SRG-OS-000028-GPOS-00009, SRG-OS-000030-GPOS-00011

Check Content

Verify the operating system prevents users from disabling the tmux terminal multiplexer with the following command: $ sudo grep -i tmux /etc/shells If any output is produced, this is a finding.

Fix Text

Configure the operating system to prevent users from disabling the tmux terminal multiplexer by editing the "/etc/shells" configuration file to remove any instances of tmux.

Additional Identifiers

Rule ID: SV-230350r627750_rule

Vulnerability ID: V-230350

Group Title: SRG-OS-000028-GPOS-00009

Expert Comments

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