Title

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

Check Content

Note: If no NFS mounts are configured, this requirement is Not Applicable. Verify RHEL 9 has the "nodev" option configured for all NFS mounts with the following command: $ grep nfs /etc/fstab 192.168.22.2:/mnt/export /data nfs4 rw,nosuid,nodev,noexec,sync,soft,sec=krb5:krb5i:krb5p If the system is mounting file systems via NFS and the "nodev" option is missing, this is a finding.

Fix Text

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

Additional Identifiers

Rule ID: SV-257854r1044934_rule

Vulnerability ID: V-257854

Group Title: SRG-OS-000480-GPOS-00227

Expert Comments

CCIs tied to check.

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