Characterizing Pixel Tracking through the Lens of Disposable Email Services Hang Hu, Peng Peng, Gang Wang Department of Computer Science, Virginia Tech fhanghu, pengp17,
[email protected] Abstract—Disposable email services provide temporary email services are highly popular. For example, Guerrilla Mail, one addresses, which allows people to register online accounts without of the earliest services, has processed 8 billion emails in the exposing their real email addresses. In this paper, we perform past decade [3]. the first measurement study on disposable email services with two main goals. First, we aim to understand what disposable While disposable email services allow users to hide their email services are used for, and what risks (if any) are involved real identities, the email communication itself is not necessar- in the common use cases. Second, we use the disposable email ily private. More specifically, most disposable email services services as a public gateway to collect a large-scale email dataset maintain a public inbox, allowing any user to access any for measuring email tracking. Over three months, we collected a dataset from 7 popular disposable email services which contain disposable email addresses at any time [6], [5]. Essentially 2.3 million emails sent by 210K domains. We show that online disposable email services are acting as a public email gateway accounts registered through disposable email addresses can be to receive emails. The “public” nature not only raises interest- easily hijacked, leading to potential information leakage and ing questions about the security of the disposable email service financial loss. By empirically analyzing email tracking, we find itself, but also presents a rare opportunity to empirically collect that third-party tracking is highly prevalent, especially in the emails sent by popular services.