Linux Kernel Vulnerability in Vsock and Virtio Transport

CVE-2026-63970

What is CVE-2026-63970?

This vulnerability in the Linux kernel affects the vsock and virtio transport layers by improperly allocating or reusing zerocopy user arguments before entering the send loop. When certain conditions are met, it may cause issues with fragmented SKB (socket buffers), subsequently leading to memory management problems. Specifically, the mishandling can result in a failure to properly reference managed fragments, which poses risks during data transmission. The issue has been addressed by ensuring that user arguments are passed correctly into the allocation function and binding them before filling the SKB, maintaining control and integrity throughout the process.

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