NetSight
high8.2

CVE-2026-31476

In the Linux kernel, the following vulnerability has been resolved: ksmbd: do not expire session on binding failure When a multichannel session binding request…

Impact

In the Linux kernel, the following vulnerability has been resolved: ksmbd: do not expire session on binding failure When a multichannel session binding request fails (e.g. wrong password), the error path unconditionally sets sess->state = SMB2_SESSION_EXPIRED. However, during binding, sess points to the target session looked up via ksmbd_session_lookup_slowpath() -- which belongs to another connection's user. This allows a remote attacker to invalidate any active session by simply sending a binding request with a wrong password (DoS). Fix this by skipping session expiration when the failed request was a binding attempt, since the session does not belong to the current connection. The reference taken by ksmbd_session_lookup_slowpath() is still correctly released via ksmbd_user_session_put().

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 5.15.1 before 6.1.168
from 6.2 before 6.6.131
from 6.7 before 6.12.80
from 6.13 before 6.18.21
from 6.19 before 6.19.11
Version 5.15

References