CVE-2026-31609
smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush() smbd_send_batch_flush() already calls smbd_free_send_io(), so we should not call it again after smbd_post_send() moved it to the batch list.
INFO
Published Date :
April 24, 2026, 3:16 p.m.
Last Modified :
April 29, 2026, 4:45 p.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to the latest version.
- Verify the patch is applied correctly.
- Reboot the system if necessary.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-31609.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-31609 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-31609
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-31609 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-31609 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Apr. 29, 2026
Action Type Old Value New Value Added CWE CWE-415 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 6.19.14 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 7.0 up to (excluding) 7.0.1 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions up to (excluding) 6.18.24 Added Reference Type kernel.org: https://git.kernel.org/stable/c/22b7c1c619d808aec4cad3dc42103345e370d107 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/27b7c3e916218b5eb2ee350211140e961bfc49be Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/a9940dcbe5cb92482c04efc7341039ddf7dbf607 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/f9a162c2bbcd0ac85bd07c5b37cf20286048b65c Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 27, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 27, 2026
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/27b7c3e916218b5eb2ee350211140e961bfc49be -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 24, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush() smbd_send_batch_flush() already calls smbd_free_send_io(), so we should not call it again after smbd_post_send() moved it to the batch list. Added Reference https://git.kernel.org/stable/c/22b7c1c619d808aec4cad3dc42103345e370d107 Added Reference https://git.kernel.org/stable/c/a9940dcbe5cb92482c04efc7341039ddf7dbf607 Added Reference https://git.kernel.org/stable/c/f9a162c2bbcd0ac85bd07c5b37cf20286048b65c