CVE-2026-64393
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: run set info with opener credentials
SMB2 SET_INFO handlers call path-based VFS helpers after checking the access mask granted to the SMB handle. Those helpers perform their owner, inode permission and LSM checks using the current ksmbd worker credentials.
Run the complete SET_INFO dispatch with the credentials captured when the handle was opened. This also removes the separate security information credential setup and keeps all SET_INFO classes under one credential scope.
Direct override_creds() is used because it can nest with the request credential overrides already used by rename and link helpers.
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: 0.70%
- Percentil entre todas las CVEs puntuadas: 52
- 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 access75 % - Impacto principal
T1565.001Stored Data Manipulationimpact70 % - Impacto secundario
T1078.003Local Accountsstealth · persistence · privilege escalation · initial access65 %
Vulnerabilidad SMB2 en kernel Linux (AV:N, PR:N, UI:N) que permite bypass de controles de acceso mediante credenciales improvisas en SET_INFO, afectando integridad de datos y permisos de archivo.
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
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/0ce682867fd506f61f40c76bde7e4205bde34e87
- https://git.kernel.org/stable/c/20ee516a62989a8d505ee432f9e59525ea23984e
- https://git.kernel.org/stable/c/5cbabf3a71575cd31bc7785d92d4ab42338a654b
- https://git.kernel.org/stable/c/8cc9ec711f5255167247a9ab6a7179b787426ed7
- https://git.kernel.org/stable/c/b35afd5cf8fab236ef21117e42ee45691d4ffa7b
- https://git.kernel.org/stable/c/b383bcad3d2fe634b26efbce53e22bbb5753a520
JSON original (NVD)
Mostrar
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