AlmaLinux OS 9 must mount /dev/shm with the nodev option.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-269314	ALMA-09-026530	SV-269314r1050196_rule		Medium

Description

The "nodev" mount option causes the system to not interpret character or block special devices. Executing character or block special devices from untrusted file systems increases the opportunity for nonprivileged users to attain unauthorized administrative access. The only legitimate location for device files is the "/dev" directory located on the root partition, with the exception of chroot jails if implemented.

STIG	Date
CloudLinux AlmaLinux OS 9 Security Technical Implementation Guide	2025-05-22

Details

Check Text (C-73345r1048318_chk)

Verify "/dev/shm" is mounted with the "nodev" option with the following command:

$ mount | grep /dev/shm

tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,noexec,seclabel,size=2097152k,inode64)

If the /dev/shm file system is mounted without the "nodev" option, this is a finding.

Fix Text (F-73246r1048319_fix)

Modify "/etc/fstab" to use the "nodev" option on the "/dev/shm" file system.