Everyone is Different: Client-side Diversification for Defending Against Extension Fingerprinting Erik Trickel, Arizona State University; Oleksii Starov, Stony Brook University; Alexandros Kapravelos, North Carolina State University; Nick Nikiforakis, Stony Brook University; Adam Doupé, Arizona State University https://www.usenix.org/conference/usenixsecurity19/presentation/trickel This paper is included in the Proceedings of the 28th USENIX Security Symposium. August 14–16, 2019 • Santa Clara, CA, USA 978-1-939133-06-9 Open access to the Proceedings of the 28th USENIX Security Symposium is sponsored by USENIX. Everyone is Different: Client-side Diversification for Defending Against Extension Fingerprinting Erik Trickel?, Oleksii Starov†, Alexandros Kapravelos‡, Nick Nikiforakis†, and Adam Doupé? ?Arizona State University †Stony Brook University {etrickel, doupe}@asu.edu {ostarov, nick}@cs.stonybrook.edu ‡North Carolina State University
[email protected] Abstract by users, as they see fit, by installing browser extensions. Namely, Google Chrome and Mozilla Firefox, the browsers Browser fingerprinting refers to the extraction of attributes with the largest market share, offer dedicated browser exten- from a user’s browser which can be combined into a near- sion stores that house tens of thousands of extensions. In turn, unique fingerprint. These fingerprints can be used to re- these extensions advertise a wide range of additional features, identify users without requiring the use of cookies or other such as enabling the browser to store passwords with online stateful identifiers. Browser extensions enhance the client- password managers, blocking ads, and saving articles for later side browser experience; however, prior work has shown that reading. their website modifications are fingerprintable and can be From a security perspective, the ability to load third-party used to infer sensitive information about users.