AlmaLinux OS 9 must prevent files with the setuid and setgid bit set from being executed on file systems that are imported via Network File System (NFS).

Severity
Group ID
Group Title
Version
Rule ID
Date
STIG Version
mediumV-269287SRG-OS-000480-GPOS-00227ALMA-09-023450SV-269287r1050169_rule2025-02-201
Description
The "nosuid" mount option causes the system not to execute "setuid" and "setgid" files with owner privileges. This option must be used for mounting any file system not containing approved "setuid" and "setguid" files. Executing files from untrusted file systems increases the opportunity for nonprivileged users to attain unauthorized administrative access.
ℹ️ Check
Note: If no NFS mounts are configured, this requirement is Not Applicable. Verify AlmaLinux OS 9 has the "nosuid" 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 "nosuid" option is missing, this is a finding.
✔️ Fix
Update each NFS mounted file system to use the "nosuid" option on file systems that are being imported via NFS.