Commercial Anti-Smishing Tools and Their Comparative Effectiveness Against Modern Threats
Daniel Timko, Muhammad Lutfor Rahman
TL;DR
This study addresses the rising threat of SMS-based phishing by developing a test bed and releasing a public fresh-smishing dataset (smishtank) to benchmark commercial anti-smishing tools. It performs a three-way comparative evaluation across bulk messaging services, mobile carriers, and third-party anti-smishing apps using 20 smishing and 20 benign messages, and analyzes the blocking behavior at each layer. The results reveal substantial gaps: many tools provide limited additional protection beyond carrier filtering, with notable false positives in some apps and limited cross-tool overlap. The findings offer actionable insights for researchers and industry, highlighting the need for improved detection—especially zero-day smishing—across all three layers and suggesting concrete recommendations such as API access controls, explicit opt-in mechanisms, and ML-driven approaches.
Abstract
Smishing, also known as SMS phishing, is a type of fraudulent communication in which an attacker disguises SMS communications to deceive a target into providing their sensitive data. Smishing attacks use a variety of tactics; however, they have a similar goal of stealing money or personally identifying information (PII) from a victim. In response to these attacks, a wide variety of anti-smishing tools have been developed to block or filter these communications. Despite this, the number of phishing attacks continue to rise. In this paper, we developed a test bed for measuring the effectiveness of popular anti-smishing tools against fresh smishing attacks. To collect fresh smishing data, we introduce Smishtank.com, a collaborative online resource for reporting and collecting smishing data sets. The SMS messages were validated by a security expert and an in-depth qualitative analysis was performed on the collected messages to provide further insights. To compare tool effectiveness, we experimented with 20 smishing and benign messages across 3 key segments of the SMS messaging delivery ecosystem. Our results revealed significant room for improvement in all 3 areas against our smishing set. Most anti-phishing apps and bulk messaging services didn't filter smishing messages beyond the carrier blocking. The 2 apps that blocked the most smish also blocked 85-100\% of benign messages. Finally, while carriers did not block any benign messages, they were only able to reach a 25-35\% blocking rate for smishing messages. Our work provides insights into the performance of anti-smishing tools and the roles they play in the message blocking process. This paper would enable the research community and industry to be better informed on the current state of anti-smishing technology on the SMS platform.
