Title

RHEL 9 must prevent code from being executed on file systems that are imported via Network File System (NFS). (Cat II impact)

Discussion

The "noexec" mount option causes the system not to execute binary files. This option must be used for mounting any file system not containing approved binary as they may be incompatible. Executing files 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 "noexec" 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 "noexec" option is missing, this is a finding.

Fix Text

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

Additional Identifiers

Rule ID: SV-257855r1044936_rule

Vulnerability ID: V-257855

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

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.