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 fails (e.g. wrong password), the error path unconditionally sets sess->state =…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.50%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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().
- CVSS 3.1
- 8.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
- EPSS
- 0.50% probability · 41th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3Patch
- https://git.kernel.org/stable/c/4642ea35c03cf3d3558c009df4757cdb7af3f82d
- https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1ccPatch
- https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9Patch
- https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340fPatch
- https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429debPatch
- https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.