Skip to main content

Boteraser | Website and Server Security Solutions

🛡️ CVE-2025-39932 — kernel

🔴 CVSS 9.8 — Critical ✅ No Known Exploit NVD
9.8
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

smb: client: let smbd_destroy() call disable_work_sync(&info->post_send_credits_work)

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);

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.

Affected software

CVE-2025-39932 is recorded against 2 packages.

  • kernel (from 6.13.0 up to 6.16.9)
  • linux-kernel

Timeline and source

Published on 4 October 2025 and last revised on 12 August 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

git.kernel.org (Web)
git.kernel.org (Web)
git.kernel.org (Web)
github.com (Advisory)
nvd.nist.gov (Advisory)
git.kernel.org (Package)

CVE-2025-39932 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity Critical
CVSS Score 9.8
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE N/A
Public Exploit ✅ No
Source NVD
Published 2025-10-04
Updated 2026-08-20
Modified 2026-08-12

Affected Packages

Software From version Fixed in
kernel 6.13.0 6.16.9
linux-kernel — —

Similar Threats

Exploit Protection

Are you running kernel?

CVE-2025-39932 carries CVSS 9.8 Critical rating. BotEraser checks your installation against this and other known CVE records, and blocks IPs associated with exploit activity.

Check My Site For CVE-2025-39932 →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.