RHEL 9 must require a unique superusers name upon booting into single-user and maintenance modes.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-257789 | RHEL-09-212020 | SV-257789r1102056_rule | CCI-000213 | high |
| Description | ||||
| Having a nondefault grub superuser username makes password-guessing attacks less effective. | ||||
| STIG | Date | |||
| Red Hat Enterprise Linux 9 Security Technical Implementation Guide | 2025-05-14 | |||
Related Frameworks
4 paths across 3 frameworks
Related Frameworks
NIST 800-531 mapping
AC-3
1.00
- DISA · 2 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
NIST 800-1712 mappings
3.1.1
1.00
- DISA · 2 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
- NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
3.1.2
1.00
- DISA · 2 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
- NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent
CCI1 mapping
CCI-000213
1.00
- DISA · 2 · disa_xccdf · related
Details
Check Text (C-257789r1102056_chk)
Verify the boot loader superuser account has been set with the following command:
$ sudo grep -A1 "superusers" /etc/grub2.cfg
set superusers="<accountname>"
export superusers
password_pbkdf2 <accountname> ${GRUB2_PASSWORD}
Verify <accountname> is not a common name such as root, admin, or administrator.
If superusers contains easily guessable usernames, this is a finding.
Fix Text (F-61454r1069355_fix)
Configure RHEL 9 to have a unique username for the grub superuser account.
Edit the "/etc/grub.d/01_users" file and add or modify the following lines with a nondefault username for the superuser account:
set superusers="<accountname>"
export superusers
Once the superuser account has been added, update the grub.cfg file by running:
Regenerate the GRUB configuration:
$ sudo grub2-mkconfig -o /boot/grub2/grub.cfg
Reboot the system:
$ sudo reboot