RHEL 9 must mount /dev/shm with the nodev option.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-257863 | RHEL-09-231110 | SV-257863r958804_rule | CCI-001764 | 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 | |||
| Red Hat Enterprise Linux 9 Security Technical Implementation Guide | 2025-05-14 | |||
Details
Check Text (C-257863r958804_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,nodev,nosuid,noexec,seclabel)
If the /dev/shm file system is mounted without the "nodev" option, this is a finding.
Fix Text (F-61528r925575_fix)
Modify "/etc/fstab" to use the "nodev" option on the "/dev/shm" file system.