The researcher has created a website that uses installed Google Chrome extensions to create a digital fingerprint of the browser and track the user on the Internet. On June 19, developer z0cc created a fingerprint Extension Fingerprints website that can generate a tracking hash based on Google Chrome extensions installed in the browser.
When creating an extension for the Chrome browser, you can declare certain assets as “web accessible resources” that web pages or other extensions can access. Resources can be used to check installed extensions and create a fingerprint of the visitor’s browser based on a combination of the extensions found.
The Extension Fingerprints website checks the visitor’s browser for the presence of an extension from 1170 popular extensions available in the Google Chrome store. Based on a combination of installed extensions, the website generates a tracking hash that can be used to track the browser.
The Extensions Fingerprints website only works with Chromium browsers and extensions from the Chrome store. The site can work with Microsoft Edge, but it needs to be changed to use extension IDs from the Microsoft store. The site does not support Mozilla Firefox because Firefox extension IDs are unique for each browser instance.
Moreover, according to the researcher, the most popular extension is ublock. Also, the presence of more than 3 extensions makes the browser fingerprint unique. Extension Fingerprints was released as an open source React project on GitHub, so any user can see how to request for installed extensions.