Out-of-Bounds Access in Linux Kernel Mailbox Controller

CVE-2026-43281

What is CVE-2026-43281?

A vulnerability exists in the Linux kernel's mailbox controller that permits out-of-bounds memory access. This occurs when the #mbox-cells property is incorrectly set to zero in the device tree, leading to potential memory corruption. If the mailbox controller fails to provide necessary function pointers for memory management, the default behavior of fw_mbox_index_xlate() is triggered, which lacks proper bounds checking. This flaw could allow malicious entities to exploit the memory access, resulting in system instability or unauthorized access to critical data.

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