After poking around the Windows Vista networking stack, Symantec researchers have tried out privilege-escalation attacks on an early version of the Windows XP successor.

In a second report on Vista, Symantec takes on a security feature called User Account Control (UAC), in the operating system. The feature runs a Vista PC with fewer user privileges to prevent malicious code from being able to do as much damage as on a PC running in administrator mode, a typical setting on Windows XP.
ZDNet