CVE-2026-53271
- Source
- https://cve.org/CVERecord?id=CVE-2026-53271
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53271.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-53271
- Downstream
- Related
- Published
- 2026-06-25T08:39:56Z
- Modified
- 2026-08-12T03:51:44Z
- Summary
- ksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers
smb2_oplock_break_noti() and smb2_lease_break_noti() read opinfo->conn into a local with neither READ_ONCE() nor a NULL check. Both run from oplock_break() after opinfo_get_list() has dropped ci->m_lock, so a concurrent SMB2 LOGOFF (session_fd_check()) can set op->conn = NULL under ci->m_lock within that window. ksmbd_conn_r_count_inc(conn) then writes through NULL at offset 0xc4 -- a remotely triggerable oops.
Guard both reads the way compare_guid_key() already does: read opinfo->conn with READ_ONCE() and return early if it is NULL, before allocating the work struct so nothing leaks. A NULL conn means the client is gone and the break is moot, so return 0; oplock_break() treats that as success and runs the normal teardown.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53271.json" }- References
-
- https://git.kernel.org/stable/c/1ff58dcfcab434ebb51649da33774fbb8e1f7b67
- https://git.kernel.org/stable/c/75e33deda658c1ab3a9336cbdb1436536f9b3660
- https://git.kernel.org/stable/c/945a86b21b40fb17183f5b27461baa6f03e2467f
- https://git.kernel.org/stable/c/b003086d76968298f22e7cf62239833b5a3a06b1
- https://git.kernel.org/stable/c/e735dbd489e3ea02be78dba991056fe1138be51e
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53271.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-53271
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced8df4bcdb0a4232192b2445256c39b787d58ef14dFixed945a86b21b40fb17183f5b27461baa6f03e2467f
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedc8efcc786146a951091588e5fa7e3c754850cb3cFixed1ff58dcfcab434ebb51649da33774fbb8e1f7b67Fixede735dbd489e3ea02be78dba991056fe1138be51eFixed75e33deda658c1ab3a9336cbdb1436536f9b3660Fixedb003086d76968298f22e7cf62239833b5a3a06b1
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introduced6.6.32Fixed6.6.143
Affected versions
v6.*
Linux / Kernel
Package
- Name
- Kernel