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 = 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().
EPSS 0.25% · 48.8th percentile
Risk Scores
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | *, 6.1.168, 6.12.80 |
| linux | linux_kernel | 0, 0, 0 |
Timeline
- Apr 22, 2026 CVE Published
- Apr 23, 2026 Security Advisory
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
- May 22, 2026 EPSS Score
- May 23, 2026 EPSS Score
- May 24, 2026 EPSS Score
- May 25, 2026 EPSS Score
- May 26, 2026 EPSS Score
- May 27, 2026 EPSS Score
References
- https://git.kernel.org/stable/c/f5300690c23c5ac860499bb37dbc09cf43fd62e6 url
- https://git.kernel.org/stable/c/6fafc4c4238e538969f1375f9ecdc6587c53f1cc url
- https://git.kernel.org/stable/c/1d1888b4a7aec518b707f6eca0bf08992c0e8da3 url
- https://git.kernel.org/stable/c/a897064a457056acb976e20e3007cdf553de340f url
- https://git.kernel.org/stable/c/e0e5edc81b241c70355217de7e120c97c3429deb url
- https://git.kernel.org/stable/c/9bbb19d21ded7d78645506f20d8c44895e3d0fb9 url
- https://nvd.nist.gov/vuln/detail/CVE-2026-31476 advisory
- https://lists.debian.org/debian-lts-announce/2026/05/msg00004.html advisory
- https://lists.debian.org/debian-lts-announce/2026/05/msg00005.html advisory
- https://lists.debian.org/debian-security-announce/2026/msg00154.html advisory
- https://lists.debian.org/debian-security-announce/2026/msg00148.html advisory