CVE-2025-0689
Published: 03 March 2025
Description
Adversaries may use bootkits to persist on systems.
Security Summary
CVE-2025-0689 is a heap-based buffer overflow vulnerability (CWE-120) in the GRUB bootloader's UDF filesystem module. The flaw occurs when reading data from disk, as the module uses user-controlled data length metadata from the filesystem to allocate internal buffers. While iterating through disk sectors, GRUB assumes the actual read size from disk is always smaller than the allocated buffer size, which is not guaranteed. A crafted UDF filesystem image can trigger the overflow, corrupting critical data.
The vulnerability has a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), indicating high impact. A local attacker with no privileges can exploit it by tricking a user into loading or booting from a malicious UDF filesystem image, such as via removable media. Successful exploitation may lead to arbitrary code execution, potentially bypassing secure boot protections.
Mitigation details are available in vendor advisories, including Red Hat's security page at https://access.redhat.com/security/cve/CVE-2025-0689, the associated Bugzilla ticket at https://bugzilla.redhat.com/show_bug.cgi?id=2346122, and the GRUB development mailing list discussion at https://lists.gnu.org/archive/html/grub-devel/2025-02/msg00024.html. Security practitioners should review these resources for patches, updated GRUB packages, and deployment guidance.
Details
- CWE(s)
Affected Products
MITRE ATT&CK Enterprise Techniques
Why these techniques?
Heap-based buffer overflow in GRUB's UDF filesystem module from crafted disk image enables arbitrary code execution during pre-OS boot, bypassing secure boot protections. This facilitates exploitation for privilege escalation (T1068), defense evasion (T1211), and bootkit deployment (T1542.003).