December 03, 2010, 4:44 PM — Be careful the next time you visit some of the Web's most popular porn, news, and torrent sites as they could be peeking at your browser history without your consent. Researchers at University of California, San Diego have discovered that 485 of the 50,000 most popular Websites in the world are exploiting a flaw that lets them read your browser's Web history. The offending sites include YouPorn.com, Gamesfreak.com, Newsmax.com, and TwinCities.com, according to the researchers.
If you want to make sure you're protecting your Web browsing history from bad actors, read on to learn how history hijacking is done and how you can prevent it.
CSS is a Web development language that controls many elements of a Web page's layout and is a commonly used tool among Web developers. One property of CSS is the "a:visited" property that displays visited Web links in a different color (typically purple) from links you haven't visited (typically blue). These properties are stored by your browser so that it can display the appropriate color for every link you come across on the Web.
Although the researchers found 485 sites are exploiting the history-sniffing flaw, 46 of those sites are actively downloading your browser history. The researchers also found that another 17 sites for a total of 63 are transferring your browsing history to their network, but couldn't confirm the sites were using the information collected. The majority of sites, according to the UC San Diego researchers, are only inspecting the style properties and nothing more.