What is CVE-2026-43255?

CVE-2026-43255 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 2.6.22 onward and patched in 5.10.252, 5.15.202, 6.1.165 and others. CVE-2026-43255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43255?

CVE-2026-43255 has a CVSS score of 5.5 out of 10, rated Medium severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Is there a patch available for CVE-2026-43255?

Yes, CVE-2026-43255 has been patched. Fixed versions include 5.10.252, 5.15.202, 6.1.165 and others. If you are running Linux kernel 2.6.22 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43255 actively exploited?

CVE-2026-43255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-43255

Medium

In the Linux kernel, the following vulnerability has been resolved: wifi: libertas: fix WARNING in usb_tx_block The function usb_tx_block() submits cardp->tx_urb without ensuring that any previous transmission on this URB has completed. If a second call occurs while the URB is still active (e.g. during rapid firmware loading), usb_submit_urb() detects the active state and triggers a warning: 'URB submitted while active'. Fix this by enforcing serialization: call usb_kill_urb() before submitting the new request. This ensures the URB is idle and safe to reuse.

Package Linux Kernel

Published 2026-05-06

Last modified 2026-05-11

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

5.5

out of 10

Medium

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

High

Vector string

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

Affected versions

Linux kernel versions 2.6.22 and later are affected. Fixed in 5.10.252, 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.16, 6.19.6, 7.0 and their respective stable series.

Affected from

≥ 2.6.22

Fixed in

✓ 5.10.252 5.10.x ✓ 5.15.202 5.15.x ✓ 6.1.165 6.1.x ✓ 6.6.128 6.6.x ✓ 6.12.75 6.12.x ✓ 6.18.16 6.18.x ✓ 6.19.6 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43255 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/2902a9b4415a6bafc9b1e5dd360f065d757a0bb7
Patch
Kernel patch commit
https://git.kernel.org/stable/c/3308c7504e093b22e91a4468470309cee2e26b83
Patch
Kernel patch commit
https://git.kernel.org/stable/c/498525d8358d6d20918787e59736d5b6a021e9fd
Patch

8 patch commits total View all on NVD

Details

CVE ID CVE-2026-43255

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-05-06

Modified 2026-05-11

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43255?

CVE-2026-43255 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 2.6.22 onward and has been patched in 5.10.252, 5.15.202, 6.1.165 and others. CVE-2026-43255 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43255?

CVE-2026-43255 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Is there a patch available for CVE-2026-43255?

Yes — CVE-2026-43255 has been patched. Fixed versions include 5.10.252, 5.15.202, 6.1.165 and others. If you are running Linux kernel 2.6.22 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43255 actively exploited?

No — CVE-2026-43255 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.