CVE-2025-39819
Estado: ModificadaMedia (5.5)—
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.
Leer descripción completaMostrar menos
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.15%
- Percentil entre todas las CVEs puntuadas: 3
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (2)
CWE
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/3fc11ff13fbc2749871d6ac2141685cf54699997
- https://git.kernel.org/stable/c/4191ea1f0bb3e27d65c5dcde7bd00e709ec67141
- https://git.kernel.org/stable/c/4735f5991f51468b85affb8366b7067248457a71
- https://git.kernel.org/stable/c/ab529e6ca1f67bcf31f3ea80c72bffde2e9e053e
- https://git.kernel.org/stable/c/cc82c6dff548f0066a51a6e577c7454e7d26a968
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
JSON original (NVD)
Mostrar
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}
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