RHEL 8 must ensure session control is automatically started at shell initialization.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230349	RHEL-08-020041	SV-230349r917920_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-000028-GPOS-00009, SRG-OS-000030-GPOS-00011

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

Details

Check Text ( C-33018r880734_chk )
Verify the operating system shell initialization file is configured to start each shell with the tmux terminal multiplexer with the following commands: Determine if tmux is currently running: $ sudo ps all \| grep tmux \| grep -v grep If the command does not produce output, this is a finding. Determine the location of the tmux script: $ sudo grep -r 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: $ sudo 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 "tmux" is not configured as the example above, is commented out, or is missing, this is a finding.

Check Text ( C-33018r880734_chk )

Verify the operating system shell initialization file is configured to start each shell with the tmux terminal multiplexer with the following commands:

Determine if tmux is currently running:
$ sudo ps all | grep tmux | grep -v grep

If the command does not produce output, this is a finding.

Determine the location of the tmux script:
$ sudo grep -r 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:
$ sudo 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 "tmux" is not configured as the example above, is commented out, or is missing, this is a finding.

Fix Text (F-32993r880735_fix)
Configure the operating system to initialize the tmux terminal multiplexer as each shell is called by adding the following lines to a custom.sh shell script in the /etc/profile.d/ directory: if [ "$PS1" ]; then parent=$(ps -o ppid= -p $$) name=$(ps -o comm= -p $parent) case "$name" in (sshd\|login) tmux ;; esac fi This setting will take effect at next logon.