White Hat Uses Foursquare Privacy Hole to Capture 875K Check-Ins

If you have checked in with Foursquare in San Francisco in the last three weeks, Jesper Andersen probably knows where and when — even if you’ve set your check-ins to be published to friends only. Andersen, a coder who recently built a service called Avoidr that helps you avoid social network “friends” you don’t really like, figured out that Foursquare had a privacy leak because of how it published user check-ins on web pages for each location.

Full Article (Threat Level - wired.com)