CVE-2026-43103

Local crash via unchecked lapbether type change

Published May 6, 2026 · Updated May 6, 2026

Improper device-type handling in Linux Kernel allows local users to crash the kernel through a lapbether backing-device type change. lapbeth_device_event() fails to reject NETDEV_PRE_TYPE_CHANGE before bonding changes the backing device away from ARPHRD_ETHER, breaking an assumption in lapbeth_data_transmit(). Exploitation requires low-privileged local access and an active lapbether interface involved in the bonding change; the reported consequence is availability loss only.

CVSS severity5.5
Medium
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper device-type handling in Linux Kernel allows local users to crash the kernel through a lapbether backing-device type change. lapbeth_device_event() fails to reject NETDEV_PRE_TYPE_CHANGE before bonding changes the backing device away from ARPHRD_ETHER, breaking an assumption in lapbeth_data_transmit(). Exploitation requires low-privileged local access and an active lapbether interface involved in the bonding change; the reported consequence is availability loss only.

The record

CVE
CVE-2026-43103
Published
May 6, 2026
Updated
May 6, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2026CVE publishedPublication date reported by the CVE source.
  2. May 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.6.24
  2. Affected versionversion=872254dd6b1f80cb95ee9e2e22980888533fc293 <328bb2cff5c2ed973f595ded769e15f4b7a117be
  3. Affected versionversion=872254dd6b1f80cb95ee9e2e22980888533fc293 <363a38044b8cd5b496d241651a1fb666e7c5fe3e
  4. Affected versionversion=872254dd6b1f80cb95ee9e2e22980888533fc293 <63851f60781aa89258c8f0952cd13940aab0888e
  5. Affected versionversion=872254dd6b1f80cb95ee9e2e22980888533fc293 <b117056768ab7deb434e7d72065e48d2083a0c2a
  6. Affected versionversion=872254dd6b1f80cb95ee9e2e22980888533fc293 <b120e4432f9f56c7103133d6a11245e617695adb

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=2.6.24; version=872254dd6b1f80cb95ee9e2e22980888533fc293 <328bb2cff5c2ed973f595ded769e15f4b7a117be; version=872254dd6b1f80cb95ee9e2e22980888533fc293 <363a38044b8cd5b496d241651a1fb666e7c5fe3e; version=872254dd6b1f80cb95ee9e2e22980888533fc293 <63851f60781aa89258c8f0952cd13940aab0888e; version=872254dd6b1f80cb95ee9e2e22980888533fc293 <b117056768ab7deb434e7d72065e48d2083a0c2a; version=872254dd6b1f80cb95ee9e2e22980888533fc293 <b120e4432f9f56c7103133d6a11245e617695adb

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5UbuntuCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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