CVE-2026-31476
What it is
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().
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of service disruption.
- Exploit odds
- 0.5% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.5% in the next 30 days (EPSS).
- Severity: 8.2 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.5% · EPSS, next 30 days
- Record status
- Modified
Affected
- Linux Kernel < 6.1.168
- Linux Kernel < 6.6.131
- Linux Kernel < 6.12.80
- Linux Kernel < 6.18.21
- Linux Kernel < 6.19.11
- Linux Kernel 5.15
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 8.2
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-31476.md and follow it. Check whether this project is affected by CVE-2026-31476. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3
- https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc
- https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9
- https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f
- https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb
- https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6
References
- https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3
- https://git.kernel.org/stable/c/4642ea35c03cf3d3558c009df4757cdb7af3f82d
- https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc
- https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9
- https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f
- https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb
- https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6