CVE-2023-4692: GNU GRUB2

High severity, CVSS 7.8. EPSS: 0.5% chance of exploitation in the next 30 days.

An out-of-bounds write flaw was found in grub2's NTFS filesystem driver. This issue may allow an attacker to present a specially crafted NTFS filesystem image, leading to grub's heap metadata corruption. In some circumstances, the attack may also corrupt the UEFI firmware heap metadata. As a result, arbitrary code execution and secure boot protection bypass may be achieved.

Affected products

• GNU GRUB2: before 2.12 (fixed in 2.12)
• Red Hat Enterprise Linux: version 8.0 only; version 9.0 only

Published 2023-10-25. Last modified 2026-07-21.