SLEM 5 with Unified Extensible Firmware Interface (UEFI) implemented must require authentication upon booting into single-user mode and maintenance.

If the system allows a user to boot into single-user or maintenance mode without authentication, any user that invokes single-user or maintenance mode is granted privileged access to all system information.

Note: If the system does not use UEFI, this requirement is not applicable.

Verify that SLEM 5 has set an encrypted GRUB bootloader password with the following command:

     > sudo cat /boot/efi/EFI/BOOT/grub.cfg | grep -i password 
     password_pbkdf2 root grub.pbkdf2.sha512.10000.03255F190F0E2F7B4F0D1C3216012309162F022A7A636771

If the GRUB bootloader password entry does not begin with "password_pbkdf2", this is a finding.

Note: If the system does not use UEFI, this requirement is not applicable.

Configure SLEM 5 to encrypt the GRUB bootloader password.

Generate an encrypted GRUB bootloader password for root with the following command:

     > grub2-mkpasswd-pbkdf2
     Enter Password:
     Reenter Password:
     PBKDF2 hash of your password is grub.pbkdf2.sha512.10000.03255F190F0E2F7B4F0D1C3216012309162F022A7A636771

Using the hash from the output, modify the "/etc/grub.d/40_custom" file and add the following two lines to add a boot password for the root entry:

     set superusers="root"
     password_pbkdf2 root grub.pbkdf2.sha512.03255F190F0E2F7B4F0D1C3216012309162F022A7A636771

Generate an updated "grub.conf" file with the new password using the following commands:

     > sudo grub2-mkconfig --output=/tmp/grub2.cfg

     > sudo mv /tmp/grub2.cfg /boot/efi/EFI/BOOT/grub.cfg