CVE-2026-45197: GPU DDK - TOCTOU affecting psFWMemContext->uiPageCatBaseRegSet
Kernel software installed and running inside a Guest VM may post improper commands to the GPU Firmware to trigger a read and/or write data outside the Guest's virtualised GPU memory.
The firmware uses data provided by the Guest VM to set up accesses to memory. It validated this before use, but a TOCTOU bug was present which allowed the earlier check results to be invalidated.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker needs the ability to run kernel software inside a Guest VM and submit improper commands to the GPU Firmware. The issue affects virtualized GPU memory handling in that guest context.
What is the impact if exploitation succeeds?
The attacker may cause the GPU Firmware to read and/or write data outside the Guest VM's virtualized GPU memory.
What is the underlying condition that enables exploitation?
The firmware validates Guest VM-provided data used to configure memory accesses, but a time-of-check to time-of-use flaw allows the earlier validation result to be invalidated before the data is used.