An Analysis of Private Browsing Modes in Modern Browsers

The authors study the security and privacy of private browsing modes recently added to all major browsers. They first propose a clean definition of the goals of private browsing and survey its implementation in different browsers. They conduct a measurement study to determine how often it is used and on what categories of sites. The results suggest that private browsing is used differently from how it is marketed. The authors then describe an automated technique for testing the security of private browsing modes and report on a few weaknesses found in the Firefox browser. Finally, they show that many popular browser extensions and plugins undermine the security of private browsing.