AlmaLinux OS 9 must require a unique superuser's name upon booting into single-user and maintenance modes.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-269138 | ALMA-09-006400 | SV-269138r1050020_rule | CCI-000213 | medium |
| Description | ||||
| Having a nondefault grub superuser username makes password-guessing attacks less effective. | ||||
| STIG | Date | |||
| CloudLinux AlmaLinux OS 9 Security Technical Implementation Guide | 2025-05-22 | |||
Details
Check Text (C-269138r1050020_chk)
Verify the boot loader superuser account has been set with the following command:
$ grep -A1 "superusers" /etc/grub2.cfg
set superusers="superman"
export superusers
password_pbkdf2 superman ${GRUB2_PASSWORD}
In this example "superman" is the actual account name, changed from the default "root".
If superusers contains easily guessable usernames, this is a finding.
Fix Text (F-73070r1049176_fix)
Configure AlmaLinux OS 9 to have a unique username for the grub superuser account using the following commands:
$ sed -ri 's/root/superman/' /etc/grub.d/01_users
$ grub2-mkconfig -o /boot/grub2/grub.cfg