Hello, More details about the potentiel vulnerability : Firefox is just starting a new process in the standard way, using CreateProcess (see <http://lxr.mozilla.org/seamonkey/source/nsprpub/pr/src/md/windows/ntmisc.c#391>). Firefox is already passing NULL to lpProcessAttributes and lpThreadAttributes, so it is using the "default" security descriptor. That might be the way that IE is using, by using a modified descriptor. Windows is the issue if the default behaviour provokes this error. But firefox in this case can't really be blamed for this problem, every applicition that launches another one will need to be fixed. Regards, Sylvain ROGER Security Consultant http://www.solucom.fr