CVE-2026-43379
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in smb_lazy_parent_lease_break_close()
opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is being accessed after rcu_read_unlock() has been called. This creates a race condition where the memory could be freed by a concurrent writer between the unlock and the subsequent pointer dereferences (opinfo->is_lease, etc.), leading to a use-after-free.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.65%
- Percentil entre todas las CVEs puntuadas: 50
- 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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access85 % - Impacto principal
T1059Command and Scripting Interpreterexecution75 %
Vulnerabilidad de use-after-free remota (CVSS AV:N) en ksmbd explotable sin autenticación. El impacto es ejecución de código en el contexto del kernel.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-416
Referencias
- https://git.kernel.org/stable/c/960699317d39f46611f4ebeb69edc567c1f4e6b6
- https://git.kernel.org/stable/c/b3568347c51c46e2cabc356bc34676df98296619
- https://git.kernel.org/stable/c/bf4d66d72e4a9e268c1012c331ce9eaedb5e2086
- https://git.kernel.org/stable/c/dbbd328cf58261ca239756fe1c0d10c9518d3399
- https://git.kernel.org/stable/c/eac3361e3d5dd8067b3258c69615888eb45e9f25
JSON original (NVD)
Mostrar
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