Here’s the latest from the world of cybertracking your web browser:

A new, extremely persistent type of online tracking is shadowing visitors to thousands of top websites, from WhiteHouse.gov to YouPorn.com.

First documented in a forthcoming paper by researchers at Princeton University and KU Leuven University in Belgium, this type of tracking, called canvas fingerprinting, works by instructing the visitor’s Web browser to draw a hidden image. Because each computer draws the image slightly differently, the images can be used to assign each user’s device a number that uniquely identifies it.

YouPorn quickly turned around and announced they they were “completely unaware that AddThis contained a tracking software that had the potential to jeopardize the privacy of our users,” and that they’d stopped using it. No such announcement came from the White House.

Pornographers 1, Washington 0.