In the Linux kernel, the following vulnerability has been resolved: smb: client: cancel reconnect work in clean_demultiplex_info() clean_demultiplex_info() cancels server->echo delayed work but not server->reconnect, which can cause a use-after-free when the demultiplex thread exits while a reconnect work is still queued: cifs_demultiplex_thread() cifs_readv_from_socket() cifs_reconnect() __cifs_reconnect() cifs_queue_server_reconn() mod_delayed_work(cifsiod_wq, &server->reconnect, 0) clean_demultiplex_info() cancel_delayed_work_sync(&server->echo) // echo canceled // reconnect NOT canceled kfree_sensitive(server) // server freed ...later, on cifsiod_wq: smb2_reconnect_server() server->srv_count // UAF read of freed server Fix this by canceling server->reconnect delayed work in clean_demultiplex_info() before the server is freed, the same way cifs_put_tcp_session() already does.
Fix
Microsoft's update · Important
- Release Notes — azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 · build 6.6.158.1-1
From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-31.
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 2
- StatusReceived → PublishedNVD modified 2026-10-19 09:15
- First seenCVSS 7.5NVD modified 2026-10-19 10:18
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 5
- https://git.kernel.org/stable/c/180380272f116dbd2b0354c5c7872e112e519149
- https://git.kernel.org/stable/c/2e5103e11a17c274715dd56cf185eeedccf686b8
- https://git.kernel.org/stable/c/7ab9ceedd860216fb97f2d8574cbe58b8906f42a
- https://git.kernel.org/stable/c/c65eae6f61d1778ff7a82e4aae4080e26f486af1
- https://git.kernel.org/stable/c/e3f6a779433d13aafb5edab59e4f9313051e8a52