AXECC: Benchmarking the Privacy and Accessibility Impact of Browser Extensions

Browser extensions are commonly used to improve the browsing experience and accessibility. However, installing extensions naturally increases the user’s risk. This work presents AXECC , a novel framework for measuring the impact of web tracking and accessibility. The AXECC framework includes static, dynamic, and accessibility analyses across multiple web pages. We utilise the AXECC framework to analyse the web tracking and accessibility impact in the wild on 21k real-world extensions collected from the Chrome Web Store. In our analysis, we identify that 15.97% of extensions (with more than 600M users) perform a type of third–party tracking in the first 60 seconds after loading. These results are highly correlated with the extension category and are consistent across different web pages. Furthermore, we find that a small number of extensions (with 65M users) alter the accessibility of a web page when browsing, and these alterations are often complex and involve more tracking. Our work reveals a significant privacy risk from web tracking within popular browser extensions, often intertwined with complex accessibility alterations.