BPF_END Logic Flaw in Linux Kernel Affecting Memory Safety

CVE-2026-43070

What is CVE-2026-43070?

A vulnerability exists in the Linux kernel related to the BPF_END operation, which improperly maintains register ID ties during byte swap operations. When a register that has undergone a BPF_END operation shares an ID with another register due to an assignment, the verification process fails to reset the destination register's ID. This oversight can result in incorrect propagation of learned bounds, potentially allowing for unsafe memory access patterns.

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