RHEL 8 operating systems booted with United Extensible Firmware Interface (UEFI) implemented must require authentication upon booting into single-user mode and maintenance.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-230234	RHEL-08-010140	SV-230234r627750_rule		High

Description
If the system does not require valid authentication before it boots into single-user or maintenance mode, anyone who invokes single-user or maintenance mode is granted privileged access to all files on the system. GRUB 2 is the default boot loader for RHEL 8 and is designed to require a password to boot into single-user mode or make modifications to the boot menu.

STIG	Date
Red Hat Enterprise Linux 8 Security Technical Implementation Guide	2021-03-04

Details

Check Text ( C-32903r567448_chk )
For systems that use BIOS, this is Not Applicable. Check to see if an encrypted root password is set. On systems that use UEFI, use the following command: $ sudo grep -iw grub2_password /boot/efi/EFI/redhat/user.cfg GRUB2_PASSWORD=grub.pbkdf2.sha512.[password_hash] If the root password does not begin with "grub.pbkdf2.sha512", this is a finding. Verify that a unique account name is set as the "superusers": $ sudo grep -iw "superusers" /boot/efi/EFI/redhat/grub.cfg set superusers="[someuniquestringhere]" export superusers If "superusers" is not set to a unique name or is missing a name, this is a finding.

Check Text ( C-32903r567448_chk )

For systems that use BIOS, this is Not Applicable.

Check to see if an encrypted root password is set. On systems that use UEFI, use the following command:

$ sudo grep -iw grub2_password /boot/efi/EFI/redhat/user.cfg

GRUB2_PASSWORD=grub.pbkdf2.sha512.[password_hash]

If the root password does not begin with "grub.pbkdf2.sha512", this is a finding.

Verify that a unique account name is set as the "superusers":

$ sudo grep -iw "superusers" /boot/efi/EFI/redhat/grub.cfg
set superusers="[someuniquestringhere]"
export superusers

If "superusers" is not set to a unique name or is missing a name, this is a finding.

Fix Text (F-32878r567449_fix)
Configure the system to require a grub bootloader password for the grub superuser account. Generate an encrypted grub2 password for the grub superuser account with the following command: $ sudo grub2-setpassword Enter password: Confirm password: Edit the /boot/efi/EFI/redhat/grub.cfg file and add or modify the following lines in the "### BEGIN /etc/grub.d/01_users ###" section: set superusers="[someuniquestringhere]" export superusers

Fix Text (F-32878r567449_fix)

Configure the system to require a grub bootloader password for the grub superuser account.

Generate an encrypted grub2 password for the grub superuser account with the following command:

$ sudo grub2-setpassword
Enter password:
Confirm password:

Edit the /boot/efi/EFI/redhat/grub.cfg file and add or modify the following lines in the "### BEGIN /etc/grub.d/01_users ###" section:

set superusers="[someuniquestringhere]"
export superusers