All major browsers change the color of links users have visited. With some JavaScript, a web site can view the colors of the links in a users browser history and determine if they have visited a site. A web site can’t pull a list of sites the user has visited from their browser, but they can test a predefined list of URL’s to see if they have visited any of them.
Spyjax makes it super easy for web sites to spy on their visitors. With Ajax, thousands of links can be tested against a visitors browser history to determine which web sites have been visited.
Luckily, if you’re a Firefox user, there is SafeHistory. A Firefox add-on that restricts the marking of visited links on the basis of the originating document, defending against web privacy attacks that remote sites can use to determine your browser history at other sites.
Welcome to johnhesch.com, a blog about my life, projects, and interests. I have been blogging for over 10 years in one form or another.