While Microsoft talked up Windows Vista security at Black Hat, a researcher in another room demonstrated how to hack the operating system.

Microsoft has touted Vista as its most secure version of windows yet. Windows Vista has many layers of defense, including the firewall, running as a standard user, Internet Explorer Protected Mode, /NX support, and ASLR, which help prevent arbitrary code from running with administrative privileges.
However, Joanna Rutkowska, a Polish researcher managed to bypass the shield and get her code to work. This could be done only in the administrator mode.

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