Vulnerability 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

For systems that use BIOS, this is Not Applicable.

Verify the /boot/efi directory is mounted with the "nosuid" option with the following command:

$ sudo mount | grep '\s/boot/efi\s'

/dev/sda1 on /boot/efi type vfat (rw,nosuid,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=ascii,shortname=winnt,errors=remount-ro)

If the /boot/efi file system does not have the "nosuid" option set, this is a finding.

Fix

Configure the "/etc/fstab" to use the "nosuid" option on the /boot/efi directory.