RHEL 9 must prevent files with the setuid and setgid bit set from being executed on file systems that are used with removable media.

Documentable No

Rule ID SV-257859r991589_rule

CCI References

CCI-000366

Discussion

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.

Check Procedure

Verify file systems that are used for removable media are mounted with the "nosuid" option with the following command:

$ more /etc/fstab

UUID=2bc871e4-e2a3-4f29-9ece-3be60c835222 /mnt/usbflash vfat noauto,owner,ro,nosuid,nodev,noexec 0 0

If a file system found in "/etc/fstab" refers to removable media and it does not have the "nosuid" option set, this is a finding.

Fix Action

Configure the "/etc/fstab" to use the "nosuid" option on file systems that are associated with removable media.