Site guesses your sex via age-old web flaw

Pardon me, your browser history is showing

By Dan Goodin in San Francisco • Get more from this author

Posted in Security, 28th July 2008 22:40 GMT

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One of the problems that's plagued netizens since the inception of the world wide web that their browsers have a habit of leaking every site they've visited in the recent past. A quick stop at Blowupdolls.com, Mysecretbusinessproject.net or any other site is available to any webmaster with rudimentary coding skills.

Now the Mike on Ads blog has harnessed this privacy shortcoming into a tool that tries to predict whether the visitor is male or female. It uses a small piece of Javascript, that siphons a browser's URL history and then analyzes the sites visited to guess whether the user is a guy or gal.

Firefox, Internet Explorer and virtually every other browser on the planet are only too eager to cough up a user's site history, a point we lamented last month, when we discussed the crisis of security confidence felt by web surfers the world over. Mozilla, Microsoft and the rest of the gang have long refused to do anything about it because fixing the problem would make it hard for users to tell sites they've visited from those they haven't.

It's unclear how accurate the tool is at guessing a visitor's sex, although it did pronounce there was a 74 percent chance your reporter was male. More importantly, the tool is a reminder of just how easy it is for webmasters to track the browsing history of their visitors. Even when you turn off Javascript, they have other tricks up their sleeves that are much harder to foil, says Jeremiah Grossman, the CTO of WhiteHat Security, who brought the tool to our attention.

Of course, browsing history isn't the only way webmasters can track personal information about their visitors. We're waiting for a tool that combines history with other metrics, such as a user's IP address, geographic location, the operating system and browser model being used and the oodles of information that can be gleaned using deep-packet inspection a la Phorm and NebuAd. Then again, we wouldn't be surprised if sites are already just doing that and no one has figured it out yet. ®

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