Microsoft Security Response Center guidance
Release Notes
Vulnerability intelligence
CVE-2025-39932 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Release Notes
In the Linux kernel, the following vulnerability has been resolved: smb: client: let smbd_destroy() call disable_work_sync(&info->post_send_credits_work) In smbd_destroy() we may destroy the memory so we better wait until post_send_credits_work is no longer pending and will never be started again. I actually just hit the case using rxe: WARNING: CPU: 0 PID: 138 at drivers/infiniband/sw/rxe/rxe_verbs.c:1032 rxe_post_recv+0x1ee/0x480 [rdma_rxe] ... [ 5305.686979] [ T138] smbd_post_recv+0x445/0xc10 [cifs] [ 5305.687135] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687149] [ T138] ? __kasan_check_write+0x14/0x30 [ 5305.687185] [ T138] ? __pfx_smbd_post_recv+0x10/0x10 [cifs] [ 5305.687329] [ T138] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 5305.687356] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687368] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687378] [ T138] ? _raw_spin_unlock_irqrestore+0x11/0x60 [ 5305.687389] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687399] [ T138] ? get_receive_buffer+0x168/0x210 [cifs] [ 5305.687555] [ T138] smbd_post_send_credits+0x382/0x4b0 [cifs] [ 5305.687701] [ T138] ? __pfx_smbd_post_send_credits+0x10/0x10 [cifs] [ 5305.687855] [ T138] ? __pfx___schedule+0x10/0x10 [ 5305.687865] [ T138] ? __pfx__raw_spin_lock_irq+0x10/0x10 [ 5305.687875] [ T138] ? queue_delayed_work_on+0x8e/0xa0 [ 5305.687889] [ T138] process_one_work+0x629/0xf80 [ 5305.687908] [ T138] ? srso_alias_return_thunk+0x5/0xfbef5 [ 5305.687917] [ T138] ? __kasan_check_write+0x14/0x30 [ 5305.687933] [ T138] worker_thread+0x87f/0x1570 ... It means rxe_post_recv was called after rdma_destroy_qp(). This happened because put_receive_buffer() was triggered by ib_drain_qp() and called: queue_work(info->workqueue, &info->post_send_credits_work);