RHEL 9 must prevent special devices on file systems that are imported via Network File System (NFS).

STIG ID: RHEL-09-231065  |  SRG: SRG-OS-000480-GPOS-00227 |  Severity: medium |  CCI: CCI-000366 |  Vulnerability Id: V-257854 | 

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.

Check

Verify RHEL 9 has the "nodev" option configured for all NFS mounts with the following command:

$ cat /etc/fstab | grep nfs

192.168.22.2:/mnt/export /data nfs4 rw,nosuid,nodev,noexec,sync,soft,sec=krb5:krb5i:krb5p

Note: If no NFS mounts are configured, this requirement is Not Applicable.

If the system is mounting file systems via NFS and the "nodev" option is missing, this is a finding.

Fix

Update each NFS mounted file system to use the "nodev" option on file systems that are being imported via NFS.