Canvas fingerprinting impervious to anti-tracking software
Tue 22 Jul 2014
An internet tracking device, developed by academics, is shadowing users’ activity on thousands of popular websites, including WhiteHouse.gov, CBS and YouPorn.com, it has emerged.
An investigation led by ProPublica, an independent investigative newsroom, found that the canvas fingerprinting tracking method was being used by 5% of the top websites to trace movements of their users.
Canvas fingerprinting was invented in 2012 and has been developed primarily by a company called AddThis. It works by instructing browsers to construct a hidden image or ‘print’ which follows the user online and relays information back to the website. It then uses these unique hidden graphics to assign a number to the computer and develop a profile for every user, allowing better placement of targeted advertising.
The shadowing software has sparked particular controversy as it is very hard to block. Anti-tracking applications such as AdBlock Plus and basic browser privacy settings are no match for canvas fingerprinting.
“A frequent argument in online privacy debates is that individuals should take control of their own privacy online [but] our results suggest that even sophisticated users may not be able to do so without significant trade-offs,” said the researchers.
After the original report was released on ProPublica, a YouPorn spokesperson has confirmed that the website was unaware the tracking application was tracking its users and has since removed the AddThis programme.