CVE-2025-0686
Grub2: romfs: integer overflow when handling symlinks may lead to heap based out-of-bounds write when reading dat
- 6.4MediumCVSS base score
- 0.29%Exploitation in 30 daysEPSS · top 78% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By redhat
- 39 days later
· 39 days later
Published
- 20 months later
· 20 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | Medium6.4 | CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium6.4 | CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.29% · top 78% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.4.
Affected products
grub2
- affected ≤ 2.12
Red Hat · Red Hat Enterprise Linux 10
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 8
All versions: unaffected
Red Hat · Red Hat Enterprise Linux 9
All versions: unaffected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: unaffected
Red Hat · Red Hat OpenShift Container Platform 4
All versions: unaffected
What to do
Workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
References
References3
- https://access.redhat.com/security/cve/CVE-2025-0686 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2346121 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://lists.gnu.org/archive/html/grub-devel/2025-02/msg00024.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-5576 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-0686)Record last updated .