Hyper-V DoS PoC. This is code files of Visual Studio 2019 driver project.

1. Compile driver.
2. Enable nested virtualization for guest OS using command:

Set-VMProcessor -VMName <VMName> -ExposeVirtualizationExtensions $true

3. Run driver inside guest OS. Host OS will be rebooted or generate BSOD with HYPERVISOR_ERROR code.

Bug is present in Hyper-V from Windows Server 2019, Windows 10 with latest patches and Windows 10 insider preview, build 10.0.20206.1000 and early.

Mitigations: Simple disable nested virtualization on untrusted VM. Execute command on host server:

Set-VMProcessor -VMName <VMName> -ExposeVirtualizationExtensions $false