Title

RHEL 9 must mount /dev/shm with the nodev option. (Cat II impact)

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 Content

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

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

Additional Identifiers

Rule ID: SV-257863r925576_rule

Vulnerability ID: V-257863

Group Title: SRG-OS-000368-GPOS-00154

Expert Comments

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