Poster: A Comprehensive Categorization of SMS Scams

SMS scams have surged over the recent years. However, little empirical research has been done to understand this rising threat due to the lack of an updated dataset. In the UK, mobile network operators run a firewall to block illicit messages. To this end, we collaborate with a major UK mobile network operator, which provides us with 3.58m SMS messages flagged by their firewall. These messages originated from over 42k unique sender IDs and were sent to 2.23m mobile numbers between December 2023 and February 2024. This is the first research to examine the current threats in the SMS ecosystem and categorize illicit SMS messages into eight sectors, including spam. We present the distribution of SMS messages successfully blocked by the mobile network operator's firewall and those that successfully evade detection.