CVE-2026-52911

Status: AnalyzedHigh (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).

Read full descriptionShow less

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

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 8.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.66%
Percentile among all scored CVEs: 50
Score date: 10/5/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1210 Exploitation of Remote Serviceslateral movement75 %
Primary impactT1078.002 Domain Accountsstealth · persistence · privilege escalation · initial access65 %
Secondary impactT1098.002 Additional Email Delegate Permissionspersistence · privilege escalation60 %
Secondary impactT1552.007 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.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

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

Affected technologies (1)

Linux — Linux Kernel

CWEs

NVD-CWE-noinfo

References

Raw JSON (NVD)

Show

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