A security thinktank says it has found a vulnerability in Apple’s QuickTime multimedia player that can be exploited remotely to compromise Windows Vista PCs upgraded to Service Pack 1, as well as XP SP2. From the informations at GNUCitizen’s blog, the exploit involves a maliciously crafted media file. When a user opens the file, which can be hosted on a website, the vulnerability in QuickTime allows the hacker to take complete control of the machine, according to Petko D. Petkov. Mr Petkov stated that it is reasonably to believe that anyone knows how to exploit this vulnerability since he didn’t shared the details with anyone, and the actual vulnerability is different enough to be rather challenging for even some of the most gifted hackers out there.The Apple is notified about this issue and did not stated any official comments.