CVE-2026-64392

Estado: AnalizadaCrítica (9.1)—

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

ksmbd: use opener credentials for delete-on-close

Delete-on-close can be completed by deferred or durable handle teardown, where no request work is available. Both the base-file unlink and the ADS xattr removal consequently run with the ksmbd worker credentials and can bypass filesystem permission checks.

Run both operations with the credentials captured in struct file when the handle was opened. This preserves the authenticated user's fsuid, fsgid, supplementary groups and capability restrictions at final close.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Puntuación base: 9.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.47%
Percentil entre todas las CVEs puntuadas: 38
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto principalT1068 Exploitation for Privilege Escalationprivilege escalation70 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact65 %

Red sin privilegios (AV:N, PR:N). Vulnerabilidad en ksmbd que permite bypass de permisos de archivo al ejecutar operaciones con credenciales incorrectas, logrando escalada local (T1068) y manipulación de datos (T1565.001).

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

Application Isolation and Sandboxing Exploit Protection Update Software Vulnerability Scanning Threat Intelligence Program Restrict File and Directory Permissions

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

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    }
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