Linux Kernel Vulnerability in io_uring Handling Affects Multiple Products

CVE-2026-43442

What is CVE-2026-43442?

A vulnerability in the Linux kernel's io_uring implementation allows unprivileged users to bypass checks on physical SQE indices when using IORING_SETUP_SQE_MIXED without IORING_SETUP_NO_SQARRAY. This flaw stems from reliance on the logical SQ head position, which can be manipulated through the sq_array. The incorrect validation can lead to memory operations that exceed the allocated buffer, potentially exposing systems to security risks. The fix involves changing the cached_sq_head alignment check to ensure direct validation of the physical SQE index, thus properly managing both sq_array and NO_SQARRAY scenarios.

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