cbcvebase.
CVE-2025-39840
published 2025-09-19

CVE-2025-39840: 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…

PriorityP430high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.14%
3.7th percentile
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]

Affected

7 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.16.6-1 (forky)linux 6.16.6-1 (forky)
linuxlinux
linuxlinux>= e92eebb0d6116f942ab25dfb1a41905aa59472a8 < 9735a9dcc307427e7d6336c54171682f1bac97899735a9dcc307427e7d6336c54171682f1bac9789
linuxlinux>= e92eebb0d6116f942ab25dfb1a41905aa59472a8 < 4540f1d23e7f387880ce46d11b5cd3f27248bf8d4540f1d23e7f387880ce46d11b5cd3f27248bf8d
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.16.6-16.16.6-1
linuxlinux_kernel>= 6.14 < 6.16.66.16.6

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
osv7.1HIGH
vendor_debian7.1LOW
vendor_redhat7.1HIGH
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