USA Today reports that researchers from Symantec and VeriSign’s iDefense Intelligence have identified a vulnerability in Adobe System’s Acrobat Reader software that allows hackers to attack personal computers through trusted links. Virtually any site hosting PDF files are vulnerable to an attack. According to the researchers, these attacks can range from stealing cookies to creating malicious worms. The flaw was first revealed at a hacker conference in Germany, and exists in a plug-in that allows Acrobat users to view PDF files in web browsers…