CVE-2025-37899

Estado: ModificadaAlta (7.8)—

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix use-after-free in session logoff

The sess->user object can currently be in use by another thread, for example if another connection has sent a session setup request to bind to the session being free'd. The handler for that connection could be in the smb2_sess_setup function which makes use of sess->user.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 1.00%
Percentil entre todas las CVEs puntuadas: 61
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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation75 %
Impacto principalT1059 Command and Scripting Interpreterexecution60 %
Impacto secundarioT1499.004 Application or System Exploitationimpact50 %

CVE-2025-37899 es una use-after-free (CWE-416) en ksmbd con acceso local y privilegios de usuario (AV:L/PR:L). Permite escalada a ejecución de código o DoS. La vulnerabilidad requiere sesiones concurrentes, explotable para elevar privilegios o causar caída del daemon SMB.

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

Execution Prevention Threat Intelligence Program Restrict Web-Based Content Privileged Account Management Limit Software Installation Filter Network Traffic

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-416

Referencias

JSON original (NVD)

Mostrar

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