An authentication bypass flaw was found in GRUB due to the way that GRUB uses the UUID of a device to search for the configuration file that contains the password hash for the GRUB password protection feature. An attacker capable of attaching an external drive such as a USB stick containing a file system with a duplicate UUID (the same as in the /boot/ file system) can bypass the GRUB password protection feature on UEFI systems, which enumerate removable drives before non-removable ones. This issue was introduced in a downstream patch in Red Hats version of grub2 and does not affect the upstream package.
This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Grub2 | Gnu | - (including) | - (including) |
| Red Hat Enterprise Linux 9 | RedHat | grub2-1:2.06-70.el9_3.2 | * |
| Red Hat Enterprise Linux 9.0 Extended Update Support | RedHat | grub2-1:2.06-27.el9_0.16 | * |
| Red Hat Enterprise Linux 9.2 Extended Update Support | RedHat | grub2-1:2.06-61.el9_2.2 | * |
| Grub2 | Ubuntu | bionic | * |
| Grub2 | Ubuntu | trusty | * |
| Grub2 | Ubuntu | xenial | * |
| Grub2-signed | Ubuntu | bionic | * |
| Grub2-signed | Ubuntu | esm-infra-legacy/trusty | * |
| Grub2-signed | Ubuntu | trusty | * |
| Grub2-signed | Ubuntu | trusty/esm | * |
| Grub2-signed | Ubuntu | xenial | * |
| Grub2-unsigned | Ubuntu | bionic | * |
| Grub2-unsigned | Ubuntu | trusty | * |
| Grub2-unsigned | Ubuntu | xenial | * |