Vulnerability · Published Mar 3, 2025 · Assigned by redhat
CVE-2025-0686Grub2: romfs: integer overflow when handling symlinks may lead to heap based out-of-bounds write when reading dat
Medium 6.4
In plain English
A medium-severity out-of-bounds write in grub2. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
A flaw was found in grub2. When performing a symlink lookup from a romfs filesystem, grub's romfs filesystem module uses user-controlled parameters from the filesystem geometry to determine the internal buffer size, however, it improperly checks for integer overflows. A maliciously crafted filesystem may lead some of those buffer size calculations to overflow, causing it to perform a grub_malloc() operation with a smaller size than expected. As a result, the grub_romfs_read_symlink() may cause out-of-bounds writes when the calling grub_disk_read() function. This issue may be leveraged to corrupt grub's internal critical data and can result in arbitrary code execution by-passing secure boot protections.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | grub2 | 2.06-13+deb12u2 | DEBIAN-CVE-2025-0686 |
| Debian:13 | grub2 | 2.12-6 | DEBIAN-CVE-2025-0686 |
| Debian:14 | grub2 | 2.12-6 | DEBIAN-CVE-2025-0686 |
| Ubuntu:22.04:LTS | grub2-signed | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:24.04:LTS | grub2-signed | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:25.10 | grub2-signed | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:26.04:LTS | grub2-signed | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:26.10 | grub2-signed | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:22.04:LTS | grub2-unsigned | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:24.04:LTS | grub2-unsigned | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:25.10 | grub2-unsigned | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:26.04:LTS | grub2-unsigned | no fix listed | UBUNTU-CVE-2025-0686 |
| Ubuntu:26.10 | grub2-unsigned | no fix listed | UBUNTU-CVE-2025-0686 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| grub2 | 0 – through 2.12 | |
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 7 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
| Red Hat | Red Hat OpenShift Container Platform 4 | see references |
Weakness: CWE-787 · Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
References
- https://access.redhat.com/security/cve/CVE-2025-0686 vdb-entry, x_refsource_REDHAT
- RHBZ#2346121 issue-tracking, x_refsource_REDHAT
- https://lists.gnu.org/archive/html/grub-devel/2025-02/msg00024.html