This paper introduces adF, a novel system for analyzing the vulnerability of different devices, Operating Systems (OSes), and browsers to web fingerprinting. adF performs its measurements from code inserted in ads. We have used our system in several ad campaigns that delivered 5.40 million ad impressions. The collected data allow us to assess the vulnerability of current desktop and mobile devices to web fingerprinting. Based on our results, we estimate that 66% of desktop devices and 40% of mobile devices can be uniquely fingerprinted with our web fingerprinting system. However, the resilience to web fingerprinting varies significantly across browsers and device types, with Chrome on desktops being the most vulnerable configuration. To counter web fingerprinting, we propose ShieldF, a simple solution which blocks the reporting by browsers of those attributes that we found in the analysis of our dataset that present the most significant discrimination power. Our experiments reveal that ShieldF outperforms all anti-fingerprinting solutions proposed by major browsers (Chrome, Safari and Firefox) offering an increase in the resilience offered to web fingerprinting up to 62% for some device configurations. ShieldF is available as an add-on for any chromium-based browser. Moreover, it is readily adoptable by browser and mobile app developers. Its widespread use would lead to a significant improvement in the protection offered by browsers and mobile apps to web fingerprinting.

翻译：本文介绍了adF，一种用于分析不同设备、操作系统（OS）和浏览器对网络指纹识别脆弱性的新型系统。adF通过嵌入广告中的代码执行其测量。我们已在多个广告活动中使用该系统，共投放了540万次广告展示。收集的数据使我们能够评估当前桌面和移动设备对网络指纹识别的脆弱性。根据我们的结果，我们估计66%的桌面设备和40%的移动设备可通过我们的网络指纹识别系统被唯一标识。然而，不同浏览器和设备类型对网络指纹识别的抵抗能力存在显著差异，其中桌面版Chrome是最脆弱的配置。为应对网络指纹识别，我们提出了ShieldF，这是一种简单的解决方案，可阻止浏览器报告那些在我们数据集分析中具有最显著区分能力的属性。实验表明，ShieldF优于主流浏览器（Chrome、Safari和Firefox）提出的所有反指纹识别方案，对某些设备配置可将网络指纹识别抵抗能力提升高达62%。ShieldF可作为任何基于Chromium的浏览器的扩展插件使用，并可被浏览器和移动应用开发者轻松采用。其广泛使用将显著提升浏览器和移动应用对网络指纹识别的防护能力。