Executive brief
A vulnerability was identified in the Linux kernel's mailbox framework, which manages communication between different processors or hardware components. If a mailbox controller is initialized without a required data structure, the system may crash (kernel OOPS) during startup. This could lead to a system failure or denial of service, particularly on embedded or specialized hardware platforms.
Technical details
A null pointer dereference vulnerability existed in 'drivers/mailbox/mailbox.c' within the 'mbox_controller_register' function. The code failed to verify the existence of the 'chans' array before proceeding with registration, which could lead to a kernel OOPS when the pointer was later dereferenced. This issue is primarily a robustness and stability flaw during early hardware instantiation. The fix introduces a mandatory check for 'mbox->chans' alongside existing checks for device, operations, and channel counts, ensuring the function returns -EINVAL instead of crashing.
Affected products
- Linux Linux kernel All versions prior to the June 2026 patches
Timeline
- 2026-04-13: disclosed: Initial patch authored
- 2026-06-26: advisory: CVE published
References
- https://git.kernel.org/stable/c/0f11444271110d9b5bc6316a153c6431abda899c
- https://git.kernel.org/stable/c/14aed0d4e58389cc6a88acf8610b12d3e476272b
- https://git.kernel.org/stable/c/37792091ab28ba030fd8d61184c47d4d51294170
- https://git.kernel.org/stable/c/5cc3300fab262b26c28bc2fc06df693410c3840b
- https://git.kernel.org/stable/c/6362c4a7d7e21e68cd9aa04df7cde16befba3a4b
- https://git.kernel.org/stable/c/9dd7489943324298bb0f385495795a82f1dd6507
- https://git.kernel.org/stable/c/c1aad75595fb67edc7fda8af249d3b886efa1be9