A “browser fingerprinting script” is a piece of JavaScript code that runs within a web page and works by testing the presence of certain browser features.
Today, “browser fingerprinting” is commonly used by online advertisers as a next-generation user tracking mechanism. Advertisers run different types of fingerprinting operations, creating one or more “fingerprints” for each user, and then use them to track the user as he/she accesses other websites on the internet.
Due to the intrusive way in which online advertisers currently use “browser fingerprinting,” several browser makers, including Firefox, Chrome, Opera, Brave, and Tor Browser, have developed features to detect and block these types of malicious code.
10% of Alexa's TOP 100,000 websites use "fingerprinting scripts"
In an academic paper published earlier this month, a team of academics from the University of Iowa and the University of California analyzed how popular “browser fingerprinting scripts” are used by website operators.
Using a machine learning toolkit they developed called FP-Inspector, they scanned and analyzed the top 100,000 most popular websites on the internet, according to Alexa rankings.
“We find that browser fingerprinting is present on more than 10% of the top 100,000 websites,” the research team said.
However, the research team also points out that despite the large number of websites currently using browser fingerprinting, not all scripts are used for tracking. Some fingerprinting scripts are also used to detect fraud, as automated bots tend to have the same or similar fingerprints, and fingerprinting scripts are a reliable method for detecting them.
However, the research team also analyzed which browser or JavaScript API features the scripts they were trying to capture had.
"What we realized is that browser fingerprinting scripts typically do not use a single technique (e.g., canvas fingerprinting), but combine multiple techniques together," the researchers said.
