CVE-2023-4001: Grub2: bypass the grub password protection feature

Published Jul 24, 2023
·
Updated

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 Hat's version of grub2 and does not affect the upstream package.

Other sources

https://bugzilla.redhat.com/showbug.cgi?id=2223437

The "/boot/efi/EFI/fedora/grub.cfg" configuration file allows an unprivileged user with physical access to a computer to bypass the GRUB password protection feature on many (but not all) UEFI-based systems.

Red Hat

Affected Software

4 affected components
GNU GRUB2
redhat Enterprise Linux=9.0
Fedoraproject Fedora=38
Fedoraproject Fedora=39

Event History

Jul 24, 2023
Data Sourced
via Red Hat·03:28 AM
DescriptionSeverityAffected Software
Jan 15, 2024
CVE Published
via MITRE·11:10 AM
Data Sourced
via MITRE·11:10 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the impact of CVE-2023-4001?

CVE-2023-4001 allows an unprivileged user with physical access to bypass the GRUB password protection.

2

What versions are affected by CVE-2023-4001?

CVE-2023-4001 affects GRUB2 and specific versions of Red Hat Enterprise Linux 9.0, Fedora 38, and Fedora 39.

3

How can I mitigate CVE-2023-4001?

To mitigate CVE-2023-4001, restrict physical access to servers and update your GRUB configuration file to strengthen security.

4

Is CVE-2023-4001 easy to exploit?

Yes, CVE-2023-4001 is considered easy to exploit because it requires only physical access to the machine.

5

Are there any updates available for CVE-2023-4001?

Yes, patches and updates addressing CVE-2023-4001 have been released and should be applied promptly.

Contact

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