Junglewise Threat Intelligence

CVE-2026-43140: Linux Kernel NULL pointer dereference in HID magicmouse driver

CVE-2026-43140 · Severity: medium · CVSS 5.5 · Published 2026-05-06

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability in the Linux kernel's Magic Mouse driver could allow a system crash when a specially crafted USB device is plugged in. By mimicking a legitimate Apple Magic Mouse but providing unexpected data, a malicious device can trigger a kernel failure. This primarily impacts system availability, potentially leading to a denial-of-service on the affected machine.

Technical details

A NULL pointer dereference exists in the HID magicmouse driver (drivers/hid/hid-magicmouse.c) of the Linux kernel. Malicious or 'fake' USB devices can provide custom report descriptors that bypass the input_mapping() hook, leaving the msc->input pointer uninitialized (NULL). When the driver subsequently attempts to use this pointer in the magicmouse_input_configured() function, it triggers a kernel crash. The fix introduces a check in the input_configured() hook to validate the pointer and reject the device if initialization failed. This requires physical access or the ability to emulate a USB device.

Affected products

  • Linux Linux Kernel 2.6.37 to 5.10.252, 5.11 to 5.15.202, 5.16 to 6.1.165, 6.2 to 6.6.128, 6.7 to 6.12.75, 6.13 to 6.18.16, 6.19 to 6.19.6

Timeline

  • 2026-01-09: other: Patch authored
  • 2026-05-06: disclosed: CVE published
  • 2026-05-13: advisory: NVD analysis completed

References

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