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.

From Red Hat Enterprise Linux 7 Security Technical Implementation Guide

Associated with: CCI-000213

SV-95719r1_rule 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.

Vulnerability discussion

If the system does not require valid root 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 content

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 root password is set. On systems that use UEFI, use the following command: # 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 the "root" account is set as the "superusers": # grep -iw "superusers" /boot/efi/EFI/redhat/grub.cfg set superusers="root" export superusers If "superusers" is not set to "root", this is a finding.

Fix text

Configure the system to encrypt the boot password for root. Generate an encrypted grub2 password for root with the following command: Note: The hash generated is an example. # 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="root" export superusers

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.