Microsoft Windows Kernel - Bitmap Use-After-Free

Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=686

The attached Proof-of-Concept crashes Windows 7 with special pool enabled on win32k.sys. The crashes are triggering in multiple different ways (two examples attached).


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/39647.zip