Quick answers
- Is CVE-2025-54771 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2025-54771 being exploited in the wild.
- How severe is CVE-2025-54771?
- Medium severity, with a CVSS score of 4.9, published 18 November 2025.
- Which products and versions are affected?
- GNU GRUB2.
- Is there a fix for CVE-2025-54771?
- A patch was published on 2025-11-18: Security patches released upstream Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2025-54771 attacked?
- It is attacked with local access, in an operating system.
- Am I affected by CVE-2025-54771?
- Check whether you run Gnu Grub2. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A use-after-free vulnerability exists in the grub_file_close() function of GNU GRUB. The root cause is a failure to properly manage filesystem reference counts; specifically, the code may attempt to access the filesystem structure after its associated module has been dereferenced via grub_dl_unref(). An attacker with local access could exploit this flaw to trigger a crash (Denial of Service) or potentially achieve more complex memory corruption. The vulnerability is addressed by reordering the closing sequence to ensure grub_dl_unref() is called only after the filesystem-specific close operation is complete. Patches have been released by the GRUB maintainers and are being integrated by Linux distributions.
Affected products
- GNU GRUB2
Timeline
- 2025-11-10: other: Reported to Red Hat Bugzilla
- 2025-11-18: disclosed: Public disclosure via oss-security and GNU mailing lists
- 2025-11-18: patched: Security patches released upstream