[TedDoesntTalk]

I am a little older than you and was writing c++ for windows 2000. One of the funnest things i did was write something called an MS-GINA driver. It let you completely replace that login screen with your own login screen. Think of the possibilities: write your own login screen that looks just like the original, but sends credentials to my remote server.

But if you had any bugs in your driver, BSOD all the way and there was no recovery. Complete reinstall.

edit: reference https://docs.microsoft.com/en-us/windows/win32/secauth

[zeusk]

Well if you had access to kd/windbg, you could "overwrite" drivers at load time.

[rdpintqogeogsaa]

That link 404s for me.

[TedDoesntTalk]

Try this one:

https://docs.microsoft.com/en-us/windows/win32/secauthn/gina

You can also google “MS GINA windows”

[throwaway2037]

Maybe this one? https://docs.microsoft.com/en-us/windows/win32/secauthn/gina