What is CVE-2026-43103?

CVE-2026-43103 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, affecting Linux kernel versions from 2.6.24 onward and patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-43103 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-43103?

CVE-2026-43103 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-2026-43103?

Yes, CVE-2026-43103 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 2.6.24 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-43103 actively exploited?

CVE-2026-43103 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-43103

Medium

In the Linux kernel, the following vulnerability has been resolved: net: lapbether: handle NETDEV_PRE_TYPE_CHANGE lapbeth_data_transmit() expects the underlying device type to be ARPHRD_ETHER. Returning NOTIFY_BAD from lapbeth_device_event() makes sure bonding driver can not break this expectation.

Package Linux Kernel

Published 2026-05-06

Last modified 2026-06-01

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 2.6.24 and later are affected. Fixed in 5.10.258, 5.15.209, 6.1.175, 6.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0 and their respective stable series.

Affected from

≥ 2.6.24

Fixed in

✓ 5.10.258 5.10.x ✓ 5.15.209 5.15.x ✓ 6.1.175 6.1.x ✓ 6.6.136 6.6.x ✓ 6.12.83 6.12.x ✓ 6.18.24 6.18.x ✓ 6.19.14 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-43103 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/328bb2cff5c2ed973f595ded769e15f4b7a117be
Patch
Kernel patch commit
https://git.kernel.org/stable/c/363a38044b8cd5b496d241651a1fb666e7c5fe3e
Patch
Kernel patch commit
https://git.kernel.org/stable/c/63851f60781aa89258c8f0952cd13940aab0888e
Patch

8 patch commits total View all on NVD

Details

CVE ID CVE-2026-43103

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2026-05-06

Modified 2026-06-01

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-43103?

CVE-2026-43103 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 2.6.24 onward and has been patched in 5.10.258, 5.15.209, 6.1.175 and others. CVE-2026-43103 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-43103?

CVE-2026-43103 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-2026-43103?

Yes — CVE-2026-43103 has been patched. Fixed versions include 5.10.258, 5.15.209, 6.1.175 and others. If you are running Linux kernel 2.6.24 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-43103 actively exploited?

No — CVE-2026-43103 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.