CVE-2025-39838
In the Linux kernel, the following vulnerability has been resolved:
cifs: prevent NULL pointer dereference in UTF16 conversion
There can be a NULL pointer dereference bug here. NULL is passed to __cifs_sfu_make_node without checks, which passes it unchecked to cifs_strndup_to_utf16, which in turn passes it to cifs_local_to_utf16_bytes where '*from' is dereferenced, causing a crash.
This patch adds a check for NULL 'src' in cifs_strndup_to_utf16 and returns NULL early to prevent dereferencing NULL pointer.
Found by Linux Verification Center (linuxtesting.org) with SVACE
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: 0.16%
- Percentil entre todas las CVEs puntuadas: 4
- Fecha de la puntuación: 6/10/2026
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
- CWE-476
Referencias
- https://git.kernel.org/stable/c/1f797f062b5cf13a1c2bcc23285361baaa7c9260
- https://git.kernel.org/stable/c/3c26a8d30ed6b53a52a023ec537dc50a6d34a67a
- https://git.kernel.org/stable/c/70bccd9855dae56942f2b18a08ba137bb54093a0
- 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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