MTU Validation Flaw in Linux Kernel Affects Networking Performance

CVE-2026-43092

What is CVE-2026-43092?

A vulnerability in the Linux kernel exists where the AF_XDP bind function accepts zero-copy pool configurations without proper validation against the device's Maximum Transmission Unit (MTU). When the chunk size is set to 2k, it may not accommodate the standard MTU of 1500, leading to potential performance issues. This oversight fails to check if the underlying hardware can satisfy the configured MTU relative to the XSK's frame size and the maximum segment length supported by the RX buffer chain. This could result in network instability and degraded performance.

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