Title

RHEL 9 must ensure session control is automatically started at shell initialization. (Cat II impact)

Discussion

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-000031-GPOS-00012, SRG-OS-000028-GPOS-00009

Check Content

Verify RHEL 9 shell initialization file is configured to start each shell with the tmux terminal multiplexer. Determine the location of the tmux script with the following command: $ sudo grep tmux /etc/bashrc /etc/profile.d/* /etc/profile.d/tmux.sh: case "$name" in (sshd|login) tmux ;; esac Review the tmux script by using the following example: $ cat /etc/profile.d/tmux.sh If [ "$PS1" ]; then parent=$(ps -o ppid= -p $$) name=$(ps -o comm= -p $parent) case "$name" in (sshd|login) tmux ;; esac fi If the shell file is not configured as the example above, is commented out, or is missing, this is a finding. Determine if tmux is currently running with the following command: $ sudo ps all | grep tmux | grep -v grep If the command does not produce output, this is a finding.

Fix Text

Configure RHEL 9 to initialize the tmux terminal multiplexer as each shell is called by adding the following to file "/etc/profile.d/tmux.sh": if [ "$PS1" ]; then parent=$(ps -o ppid= -p $$) name=$(ps -o comm= -p $parent) case "$name" in sshd|login) tmux ;; esac fi

Additional Identifiers

Rule ID: SV-258064r943016_rule

Vulnerability ID: V-258064

Group Title: SRG-OS-000031-GPOS-00012

Expert Comments

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