CVE-2026-52911

Estado: AnalizadaAlta (8.8)—

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

ksmbd: scope conn->binding slowpath to bound sessions only

When the binding SESSION_SETUP sets conn->binding = true, the flag stays set after the call so that the global session lookup in ksmbd_session_lookup_all() can find the session, which was not added to conn->sessions. Because the flag is connection-wide, the global lookup path will also resolve any other session by id if asked.

Tighten the global lookup so that the returned session must have this connection registered in its channel xarray (sess->ksmbd_chann_list).

Leer descripción completaMostrar menos

The channel entry is installed by the existing binding_session path in ntlm_authenticate()/krb5_authenticate() when a SESSION_SETUP completes successfully, so this condition is a strict equivalent of "this connection has been accepted as a channel of this session". Connections that have not bound to a given session cannot reach it via the global table.

The existing conn->binding gate for entering the slowpath is preserved so that non-binding connections keep the fast-path-only behavior, and the session->state check is unchanged.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 8.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.66%
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.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement75 %
Impacto principalT1078.002 Domain Accountsstealth · persistence · privilege escalation · initial access65 %
Impacto secundarioT1098.002 Additional Email Delegate Permissionspersistence · privilege escalation60 %
Impacto secundarioT1552.007 Container APIcredential access55 %

Acceso de red con privilegios (PR:L) a ksmbd (SMB kernel); impactos: sesiones vinculadas sin validación permiten suplantación de cuenta, gestión de sesiones y acceso a credenciales de canal.

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

Privileged Account Management User Account Management Network Segmentation Multi-factor Authentication Disable or Remove Feature or Program Vulnerability Scanning

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

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