Vulnerability in GNU Grub2
CVE-2023-4001
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.005 (44.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 44th percentile — 44.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- GNU Grub2
- Fedoraproject Fedora — versions 38, 39
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9 — versions 1:2.06-70.el9_3.2
- Red Hat Enterprise Linux 9.0 Extended Update Support — versions 1:2.06-27.el9_0.16
- Red Hat Enterprise Linux 9.2 Extended Update Support — versions 1:2.06-61.el9_2.2
- Red Hat Enterprise Linux — versions 9.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- access.redhat.com/errata/RHSA-2024:0437 (vendor-advisory)
- access.redhat.com/errata/RHSA-2024:0456 (vendor-advisory)
- access.redhat.com/errata/RHSA-2024:0468 (vendor-advisory)
- access.redhat.com/security/cve/CVE-2023-4001 (Third Party Advisory, vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Issue Tracking, Vendor Advisory)
- dfir.ru/2024/01/15/cve-2023-4001-a-vulnerability-in-the-downstream-grub-boot-ma… (Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2023-4001?
- CVE-2023-4001 is a medium-severity vulnerability in GNU Grub2, classified under Authentication Bypass by Spoofing. CVSS score: 6.8/10. Published 2024-01-15.
- How severe is CVE-2023-4001?
- Medium severity. CVSS v3 base score is 6.8 out of 10.
- Is CVE-2023-4001 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.