> Holy mackerel! Instances of this bug date back to 1999!

Different bug. That appears to be a trivial exhaustion of CSRSS worker =
threads through indiscriminate calls to =
MessageBox+MB_SERVICE_NOTIFICATION, which causes a DoS as no threads are =
available to serve kernel-mode requests from win32k, stalling GUI =
processes. I have done my fair share of CSRSS reversing in my better =
days, and I'm pretty sure that in Windows 2000 and later, a dedicated =
thread is used for such notifications, not just any thread, any time. =
Easily verifiable with local net sends and Spy++. It wasn't a "bug" =
either, more like a serious design flaw that ignored a very basic Win32 =
mantra ("don't do GUI in a worker thread") - not at all like this =
double-free