Linux Kernel up to 6.18.13/6.19.3 eth buffer overflow

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.18.13/6.19.3. It has been classified as critical. Affected is an unknown function of the component eth. Performing a manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2026-45952. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.13/6.19.3. It has been classified as critical. This affects an unknown code block of the component eth. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: eth: fbnic: Add validation for MTU changes Increasing the MTU beyond the HDS threshold causes the hardware to fragment packets across multiple buffers. If a single-buffer XDP program is attached, the driver will drop all multi-frag frames. While we can't prevent a remote sender from sending non-TCP packets larger than the MTU, this will prevent users from inadvertently breaking new TCP streams. Traditionally, drivers supported XDP with MTU less than 4Kb (packet per page). Fbnic currently prevents attaching XDP when MTU is too high. But it does not prevent increasing MTU after XDP is attached.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-45952 since 05/13/2026. The exploitability is told to be easy. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 06/16/2026).

Upgrading to version 6.18.14 or 6.19.4 eliminates this vulnerability. Applying the patch d7eaa006c0444a5d4671be7efe6dbb33ef8b515e/03399063aa0c67fd8bdfd69467ddb849bb3b97df/ccd8e87748ad083047d6c8544c5809b7f96cc8df is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Entryinfo

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