CVE-2025-39819

5.5 MEDIUM
Published: September 16, 2025 Modified: January 16, 2026
View on NVD

Description

In the Linux kernel, the following vulnerability has been resolved: fs/smb: Fix inconsistent refcnt update A possible inconsistent update of refcount was identified in `smb2_compound_op`. Such inconsistent update could lead to possible resource leaks. Why it is a possible bug: 1. In the comment section of the function, it clearly states that the reference to `cfile` should be dropped after calling this function. 2. Every control flow path would check and drop the reference to `cfile`, except the patched one. 3. Existing callers would not handle refcount update of `cfile` if -ENOMEM is returned. To fix the bug, an extra goto label "out" is added, to make sure that the cleanup logic would always be respected. As the problem is caused by the allocation failure of `vars`, the cleanup logic between label "finished" and "out" can be safely ignored. According to the definition of function `is_replayable_error`, the error code of "-ENOMEM" is not recoverable. Therefore, the replay logic also gets ignored.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/3fc11ff13fbc2749871d6ac2141685cf54699997
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/4191ea1f0bb3e27d65c5dcde7bd00e709ec67141
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/4735f5991f51468b85affb8366b7067248457a71
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/ab529e6ca1f67bcf31f3ea80c72bffde2e9e053e
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/cc82c6dff548f0066a51a6e577c7454e7d26a968
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory

6 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.5 / 10.0
EPSS (Exploit Probability)
0.0%
6th percentile
Exploitation Status
Not in CISA KEV

Affected Vendors

debian linux