RHEL 9 must prevent device files from being interpreted on file systems that contain user home directories.

STIG ID: RHEL-09-231045  |  SRG: SRG-OS-000368-GPOS-00154 |  Severity: medium |  CCI: CCI-001764 |  Vulnerability Id: V-257850 | 

Vulnerability Discussion

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.

Check

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

Note: If a separate file system has not been created for the user home directories (user home directories are mounted under "/"), this is automatically a finding, as the "nodev" option cannot be used on the "/" system.

$ mount | grep /home

tmpfs on /home type tmpfs (rw,nodev,nosuid,noexec,seclabel)

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

Fix

Modify "/etc/fstab" to use the "nodev" option on the "/home" directory.