CVE-2026-68381: Linux kernel · ksmbd: pin conn during async oplock break notification
Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in dab1493bc9d97947f1219d6823c2e2a28636021b : patch Linux kernel as a priority.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 9.8 |
|---|
- Patch
- Available – fixed in dab1493bc9d97947f1219d6823c2e2a28636021b, aa5d8f3f96aa11a4a54ce993c11ce8af11c546f9, 14062c74e5b25c27edcff7a2fe0dc701c930b372 +6
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: pin conn during async oplock break notification smb2_oplock_break_noti() and smb2_lease_break_noti() store a ksmbd_conn pointer in an async ksmbd_work and then queue that work on ksmbd-io. The work only increments conn->r_count, which prevents teardown from passing the pending-request wait after the increment, but it does not pin the struct ksmbd_conn object. If connection teardown races with an oplock break notification, the last conn reference can be dropped before the queued worker finishes. The worker then uses the freed conn in ksmbd_conn_write() and ksmbd_conn_r_count_dec(). Take a real conn reference when publishing the conn pointer to the async work item, and drop it after the notification work has decremented r_count. Apply the same lifetime rule to lease break notification, which uses the same work->conn pattern.
References
- nvd.nist.gov/vuln/detail/CVE-2026-68381 (opens in a new tab)
- git.kernel.org/stable/c/0f72fc9659d7f585460d43c158055df5afdcffb6 (opens in a new tab)
- git.kernel.org/stable/c/14062c74e5b25c27edcff7a2fe0dc701c930b372 (opens in a new tab)
- git.kernel.org/stable/c/6ecb252efa0b413ac3d9979fb4eec247f8fc1258 (opens in a new tab)
- git.kernel.org/stable/c/793e1c7041b93af96ff87e678329bc16aee7ba88 (opens in a new tab)
- git.kernel.org/stable/c/aa5d8f3f96aa11a4a54ce993c11ce8af11c546f9 (opens in a new tab)
- git.kernel.org/stable/c/dab1493bc9d97947f1219d6823c2e2a28636021b (opens in a new tab)