Executive brief
A vulnerability exists in the Linux kernel's driver for Arm Ethos-U neural processing units (NPUs), which are used to accelerate machine learning tasks. A local user could exploit a flaw in how the driver processes commands to corrupt internal system memory. This could lead to a complete system crash or allow an attacker to gain unauthorized elevated privileges on the device.
Technical details
An out-of-bounds write vulnerability exists in the Arm Ethos-U (accel/ethosu) driver within the Linux kernel. The root cause is an incorrect bitmask (0x7f instead of 0x7) used in the NPU_SET_IFM_REGION command within the ethosu_gem_cmdstream_copy_and_validate function. This allows a userspace caller to specify a region index up to 127, while the internal region_size array is only sized for 8 elements. When the driver subsequently uses this index to write to the heap-allocated info struct, it can overwrite up to 1016 bytes of adjacent kernel heap data. This local attack vector requires the ability to interact with the Ethos-U NPU device node. Patches have been released in stable kernel branches to enforce the correct 0x7 mask.
Affected products
- Linux Linux Kernel 6.19 to 7.1
Timeline
- 2026-05-23: disclosed: Initial patch submitted by Muhammad Bilal
- 2026-06-04: patched: Patch committed to mainline kernel
- 2026-06-25: advisory: CVE-2026-53172 published