A new persistent tracking device was recently found on websites and it is almost impossible to block. The tracker was found on the sites Whitehose.gov and an adult entertainment site. This technology was first documented by researchers at Princeton and KU Leuven University in Belgium. It is called canvas fingerprinting and it works by communicating to the user’s computer instructing it to draw up a hidden image. Because each computer draws the image differently, the images can be used to assign a number combination that uniquely identifies it.
Like other tracking devices, canvas fingerprints are used to construct profiles of users based on the websites they visit; profiles that dictate which ads, articles, and other content is displayed to them. The difference with this tracking device is that it is unusually difficult to block. It cannot be prevented through services like Adblock Plus. The researchers located canvas fingerprinting code on five percent of the top 100,000 websites. The majority of the code was located on websites that utilize social media sharing tools from AddThis.
The technology relies on the fact that each computer manufactured is unique. Each has its own set of software, settings, and specifications. Computers broadcast these differences when they connect over the Internet on occasion. Tracking companies have long pursued how to utilize those differences to identify computers for advertising purposes, especially now that the number of web users using ad blocking technologies is increasing.
Other websites that utilize the tracking device are the Canadian dating site Plentyoffish and the German digital marketer Ligatus. Richard Harris, the CEO of AddThis, stated his company began the canvas fingerprinting earlier this year in an effort to locate a suitable replacement for cookies; the traditional method used on the web for tracking websites users visit via text files saved on the computer.
Harris said that he and his company considered the consequences of privacy that canvas fingerprinting would have. The online tracking device that was found on several websites and is almost impossible to block adheres to all the rules and regulations that AddThis has on their technology. The company will not utilize the device if users decide to install the AddThis opt-out program on their computers.
Arvind Narayanan, the Princeton University professor who lead the inquiry into the AddThis tracking device, stated that web surfers should not trust AddThis solely on their word. The tracking company did not notify any of the websites they implemented their technology they would be hosting the new technology. According to the company, the reason for this secrecy was that they conduct all of their programs in real world environments to get the most accurate results in testing.
The adult content provider said that they had no idea that AddThis was implementing this tracking device on their website and had the potential to jeopardize the privacy of its users. This statement came after the website promptly removed all AddThis code off of their website. According to the researchers, AddThis has collected several million fingerprints thus far.
By Andres Loubriel