Red Hat Enterprise Linux operating systems version 7.2 or newer using Unified Extensible Firmware Interface (UEFI) must require authentication upon booting into single-user and maintenance modes.

STIG ID: RHEL-07-010491  |  SRG: SRG-OS-000080-GPOS-00048 |  Severity: high |  CCI: CCI-000213 |  Vulnerability Id: V-204440 | 

Vulnerability Discussion

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 7 and is designed to require a password to boot into single-user mode or make modifications to the boot menu.

Check

For systems that use BIOS, this is Not Applicable.

For systems that are running a version of RHEL prior to 7.2, this is Not Applicable.

Check to see if an encrypted grub superusers 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 grub superusers password does not begin with "grub.pbkdf2.sha512", this is a finding.

Fix

Configure the system to encrypt the boot password for the grub superusers account with the grub2-setpassword command, which creates/overwrites the /boot/efi/EFI/redhat/user.cfg file.

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

$ sudo grub2-setpassword
Enter password:
Confirm password:
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