CVE-2025-0689

When reading data from disk, the grub's UDF filesystem module utilizes the user controlled data length metadata to allocate its internal buffers. In certain scenarios, while iterating through disk sectors, it assumes the read size from the disk is always smaller than the allocated buffer size which is not guaranteed. A crafted filesystem image may lead to a heap-based buffer overflow resulting in critical data to be corrupted, resulting in the risk of arbitrary code execution by-passing secure boot protections.

To exploit this flaw, an attacker needs to trick a user into running grub2 with a specially crafted UDF file system image, limiting the exposure of this flaw. For this reason, this vulnerability has been rated with a Moderate severity.

The grub2 package as shipped in Red Hat Enterprise Linux 7, 8, 9 and in Red Hat OpenShift Container Platform 4 is not affected by this vulnerability because the UDF module is not built, so this issue is not applicable.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.