Title

RHEL 9 must be configured so that the Network File System (NFS) is configured to use RPCSEC_GSS. (Cat II impact)

Discussion

When an NFS server is configured to use RPCSEC_SYS, a selected userid and groupid are used to handle requests from the remote user. The userid and groupid could mistakenly or maliciously be set incorrectly. The RPCSEC_GSS method of authentication uses certificates on the server and client systems to more securely authenticate the remote mount request.

Check Content

Verify RHEL 9 has the "sec" option configured for all NFS mounts with the following command: Note: If no NFS mounts are configured, this requirement is Not Applicable. $ cat /etc/fstab | grep nfs 192.168.22.2:/mnt/export /data nfs4 rw,nosuid,nodev,noexec,sync,soft,sec=krb5p:krb5i:krb5 If the system is mounting file systems via NFS and has the sec option without the "krb5:krb5i:krb5p" settings, the "sec" option has the "sys" setting, or the "sec" option is missing, this is a finding.

Fix Text

Update the "/etc/fstab" file so the option "sec" is defined for each NFS mounted file system and the "sec" option does not have the "sys" setting. Ensure the "sec" option is defined as "krb5p:krb5i:krb5".

Additional Identifiers

Rule ID: SV-257853r925546_rule

Vulnerability ID: V-257853

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

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