Most web users know that their browser swallows cookies – the bits of code marketers, sites and others use to track your online behavior. But many, if not most, also know that cookies are easy to remove. Scores of popular spyware removal programs (some we trust include SuperAntispyware, Spybot, and Spyware Blaster) snag and delete them. Now, however, a number of popular websites, including MSN and Hulu, are using so-called “Supercookies,” that are much harder to remove.
Researchers at Sanford University and the University of California have exposed the technique, which allows sites snooping on you using Flash Cookies, some of which recreate regular HTTP cookies you delete.
At least one of the supercookies the researchers found (on Time-Warner’s Flixster.com, a movie-focused site) could actually snoop around to see if you have visited any of 1,500 other sites it tracks, including those dealing with such topics as menopause, credit repair, fertility problems.
MSN, told by the researchers about the technique being used on its sites denied knowledge of the technique and said it was contrary to its policies.
For ways to remove these supercookies or prevent Flash from using them, see this guide at Fight Identity Theft.com.