Title

RHEL 8 must prevent files with the setuid and setgid bit set from being executed on the /boot/efi directory. (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

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 Text

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

Additional Identifiers

Rule ID: SV-244530r1017337_rule

Vulnerability ID: V-244530

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

Expert Comments

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