RE: [Full-disclosure] Microsoft Windows XP/2003/Vista memory corruption 0day

["Michele Cicciotti" <mc@xxxxxxxxxx>]

> 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