A computer security researcher has found a flaw in Microsoft Corp's widely used Internet Explorer browser that he said could let hackers steal credentials to access FaceBook, Twitter and other websites.  
"Any website. Any cookie. Limit is just your imagination," said Rosario Valotta, an independent Internet security researcher based in Italy.  
Hackers can exploit the flaw to access a data file stored inside the browser known as a "cookie," which holds the login name and password to a web account, Valotta said via email.  
Once a hacker has that cookie, he or she can use it to access the same site, said Valotta, who calls the technique "cookiejacking."  
The vulnerability affects all versions of Internet Explorer, including IE 9, on every version of the Windows operating system.  
To exploit the flaw, the hacker must persuade the victim to drag and drop an object across the PC's screen before the cookie can be hijacked.