Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: audit: fix out-of-bounds read in audit_compare_dname_path() When a watch on dir=/ is combined with an fsnotify event for a single-character name directly under / (e.g., creating /a), an out-of-bounds read can occur in audit_compare_dname_path(). The helper parent_len() returns 1 for "/". In audit_compare_dname_path(), when parentlen equals the full path length (1), the code sets p = path + 1 and pathlen = 1 - 1 = 0. The subsequent loop then dereferences p[pathlen - 1] (i.e., p[-1]), causing an out-of-bounds read. Fix this by adding a pathlen > 0 check to the while loop condition to prevent the out-of-bounds access. [PM: subject tweak, sign-off email fixes]
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux Kernel | >= 6.14, < 6.16.6 |
Related Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/4540f1d23e7f387880ce46d11b5cd3f27248bf8dPatch
- https://git.kernel.org/stable/c/9735a9dcc307427e7d6336c54171682f1bac9789Patch
FAQ
What is CVE-2025-39840?
CVE-2025-39840 is a vulnerability with a CVSS score of 7.1 (HIGH). In the Linux kernel, the following vulnerability has been resolved: audit: fix out-of-bounds read in audit_compare_dname_path() When a watch on dir=/ is combined with an fsnotify event for a single-...
How severe is CVE-2025-39840?
CVE-2025-39840 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-39840?
Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.