Title

RHEL 8 must prevent files with the setuid and setgid bit set from being executed on file systems that are used with removable media. (Cat II impact)

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 unprivileged users to attain unauthorized administrative access.

Check Content

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

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

Additional Identifiers

Rule ID: SV-230305r627750_rule

Vulnerability ID: V-230305

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

Expert Comments

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