Kernel Memory Handling Flaw in Zephyr RTIO Product by Zephyr Project

CVE-2026-16511

What is CVE-2026-16511?

A significant vulnerability exists in the Zephyr RTIO implementation, where two syscall verifiers fail to validate user-supplied pointers before allowing the kernel to modify memory locations. Specifically, the lack of checks in functions like z_vrfy_rtio_sqe_cancel() and inadequate validation in z_vrfy_rtio_sqe_copy_in_get_handles() expose the kernel to potential privilege escalation attacks. With no constraints on user-mode threads, attackers can manipulate kernel data structures, thereby gaining unauthorized access and control over system resources. Mitigations have been put in place to address these weaknesses by enhancing parameter validations and enforcing permissions on RTIO contexts.

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