Poster: When Diameter Firewall Meets User Devices
Maurice Zhang, Stephen Dowhy, John Doyle, David Dunn, Joel Cornett, Sangwook Bae · 2025
A Diameter firewall is essential for mobile operators to protect their subscribers, as Diameter networks lack end-to-end authentication and heavily rely on trust among partner operators. Among the various attacks exploiting the Diameter protocol, one notable example involves falsely updating a subscriber's location and illegitimately requesting authentication data. Conventional methods, known as velocity checks, validate the originating network of messages by assessing the plausibility of subscriber movement based solely on network-provided information. However, attackers can still bypass these checks by simulating their presence in nearby or bordering countries. This poster introduces a user-interactive Diameter firewall, which incorporates user engagement by allowing subscribers to confirm suspicious requests.