CVE-2026-64397
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: serialize QUERY_DIRECTORY requests per file
smb2_query_dir() stores a pointer to its stack-allocated private data in the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the same file handle can overwrite this pointer while an iterate_dir() callback is still using it, resulting in a stack use-after-free.
Add a per-file mutex and hold it while accessing the shared directory enumeration state. The lock covers scan restart, dot entry state, readdir_data setup and iteration, and response construction. This prevents another request from replacing readdir_data.private before the current request has finished using it and also serializes the shared file position.
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: 0.70%
- Percentil entre todas las CVEs puntuadas: 52
- 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.
- Explotación
T1190Exploit Public-Facing Applicationinitial access75 % - Impacto principal
T1059Command and Scripting Interpreterexecution65 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation60 %
Vulnerabilidad crítica de uso tras liberación (CWE-416) en kernel Linux explotable remotamente sin autenticación (AV:N/PR:N). Permite ejecución de código arbitrario (C:H/I:H) con potencial escalada a root. Vector CVSS sin UI:R apunta a T1190.
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/1426fd79102539bc0ab5c8fced047ad4313b9908
- https://git.kernel.org/stable/c/2a64dbf9c739ddf7a25a066507597bf89f8f73d2
- https://git.kernel.org/stable/c/64dac2d486ec1eb18dc00968b16a230b6b75ec24
- https://git.kernel.org/stable/c/a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199
- https://git.kernel.org/stable/c/be6d26bf27499977c746abc163659915082348d8
- https://git.kernel.org/stable/c/fd22b039a5a05bc1d6818e9dcd1001fb432a829d
JSON original (NVD)
Mostrar
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