1.4.1 Ensure permissions on bootloader config are configured (Scored)

Level 1 - Server 
Level 1 - Workstation

The grub configuration file contains information on boot settings and passwords for unlocking boot options. The grub configuration is usually located at /boot/grub2/grub.cfg and linked as /etc/grub2.conf.

Setting the permissions to read and write for root only prevents non-root users from seeing the boot parameters or changing them. Non-root users who read the boot parameters may be able to identify weaknesses in security upon boot and be able to exploit them.

Run the following command and verify Uid and Gid are both 0/root and Access does not grant permissions to group or other:

# stat /boot/grub2/grub.cfg 
Access: (0600/-rw-------) Uid: ( 0/ root) Gid: ( 0/ root)

Run the following commands to set permissions on your grub configuration:

# chown root:root /boot/grub2/grub.cfg 
# chmod og-rwx /boot/grub2/grub.cfg

This recommendation is designed around the grub bootloader, if LILO or another bootloader is in use in your environment enact equivalent settings.