Vulnerability details
CVE-2025-39840
audit: fix out-of-bounds read in audit_compare_dname_path()
Official 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 scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.1High | 3.1 | CISA ADP / Vulnrichment (CISA-ADP) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
| 7.1High | 3.1 | CVEProject cvelistV5 (CNA) (Linux) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Linux | Linux | 6.14 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | e92eebb0d6116f942ab25dfb1a41905aa59472a8 ≤ v < 9735a9dcc307427e7d6336c54171682f1bac9789 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | e92eebb0d6116f942ab25dfb1a41905aa59472a8 ≤ v < 4540f1d23e7f387880ce46d11b5cd3f27248bf8d | CVEProject cvelistV5 (CNA) |
References and advisories
2Details
- Published
- 2025-09-19
- Last updated
- 2026-08-05
- State
- Published
- Assigner (CNA)
- Linux
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- None
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-125Out-of-bounds Read