Executive brief
A vulnerability in the Linux kernel's Intel graphics driver could allow a local user to cause a system crash. The issue occurs during the initial setup of the graphics hardware when certain power-saving features are unexpectedly enabled by the system BIOS. This results in a 'kernel oops' (a system error), which can disrupt operations and lead to a denial of service on affected Intel-based systems.
Technical details
A NULL pointer dereference exists in the drm/i915/dmc component of the Linux kernel. The vulnerability occurs in intel_dmc_update_dc6_allowed_count() when it is called during the hardware probe sequence before the Display Microcontroller (DMC) has been fully initialized. This happens if the BIOS leaves the hardware in a DC6 power state at boot. The driver was incorrectly using the hardware DC6 state for tracking instead of the software state, leading to an 'oops' when attempting to access uninitialized DMC structures. The fix involves transitioning the tracking mechanism to use the software-defined DC6 state. Patches have been released for multiple stable kernel branches.
Affected products
- Linux Linux Kernel 6.16 to 6.18.20, 6.19 to 6.19.10, 7.0-rc1 to 7.0-rc4
Timeline
- 2026-03-09: patched: Initial fix authored
- 2026-04-03: disclosed: CVE published