Martin Bajanik's Articles

Martin Bajanik

Role

Staff Engineer, Research

Martin Bajanik Articles

A graphic showing data leaking from one browser window to another

April 22, 2026

We found a stable Firefox identifier linking all your private Tor identities

We discovered a privacy vulnerability in Firefox Private Browsing and Tor Browser that allows websites to fingerprint and track users across origins using IndexedDB database ordering, even after closing all private windows.

October 19, 2023

Demo: Chrome Site Engagement Feature Can Leak Frequently Visited Sites

We explain how Chromium’s Lookalike Warnings and Site Engagement can leak information on frequently visited sites to untrustworthy websites.

September 14, 2022

Why Anti-Fingerprinting Techniques Don't Work in Browsers

Exploring anti-fingerprinting solutions, we discuss their effectiveness and why device identification is crucial in preventing online fraud.