RHEL 9 must ensure session control is automatically started at shell initialization.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258064	RHEL-09-412015	SV-258064r958404_rule		Medium

Description
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

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2024-06-04

Details

Check Text ( C-61805r943015_chk )
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.

Check Text ( C-61805r943015_chk )

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 (F-61729r926178_fix)
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