What is CVE-2026-43440?

CVE-2026-43440 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, classified as a Use After Free flaw (CWE-416), affecting Linux kernel versions from 6.18.16 onward. CVE-2026-43440 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43440?

CVE-2026-43440 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-43440?

No patch is currently available for CVE-2026-43440. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2026-43440 actively exploited?

CVE-2026-43440 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Use After Free (CWE-416)?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/416.html

CVE-2026-43440

High

In the Linux kernel, the following vulnerability has been resolved: net/mana: Null service_wq on setup error to prevent double destroy In mana_gd_setup() error path, set gc->service_wq to NULL after destroy_workqueue() to match the cleanup in mana_gd_cleanup(). This prevents a use-after-free if the workqueue pointer is checked after a failed setup.

Package Linux Kernel

Published 2026-05-08

Last modified 2026-05-21

CVSS version 3.1

Patch available

Not yet patched

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-416

CVE-2026-43440 is a Use After Free vulnerability

What is Use After Free?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.18.16, 6.19.6 and later are affected. No fixed version recorded yet.

Affected from

≥ 6.18.16 ≥ 6.19.6

References

The following references provide additional information about CVE-2026-43440 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/59489ce60d7412ed82fb1d8002faa3102dcd4916
Patch
Kernel patch commit
https://git.kernel.org/stable/c/6c92392602b451e3869f15ab685f8f650e942b13
Patch
Kernel patch commit
https://git.kernel.org/stable/c/87c2302813abc55c46485711a678e3c312b00666
Patch

Details

CVE ID CVE-2026-43440

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-05-08

Modified 2026-05-21

KEV No

Patch

Not yet patched

Package linux

Frequently asked questions

What is CVE-2026-43440?

CVE-2026-43440 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 6.18.16 onward . CVE-2026-43440 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43440?

CVE-2026-43440 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-43440?

No patch is currently available for CVE-2026-43440. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2026-43440 actively exploited?

No — CVE-2026-43440 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Use After Free (CWE-416)?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →