Social engineers use a false pretense and their interpersonal skills to persuade their targets to divulge sensitive information such as their usernames, passwords, or credit card numbers. Social engineering over the phone, known as vishing, is a very common, growing, and costly problem. This project aims to investigate the nature of vishing attacks and use what is learned to develop a software application that detects key vishing attack features, moving the project toward its long-term goal of developing a software system that can detect vishing attacks in real-time and warn targets.<br/><br/>To accomplish that aim, the research team is creating two corpora: 1) a set of vishing attack recordings and 2) a set of legitimate phone call recordings. The research team is developing advanced analytical techniques to identify features that differentiate vishing conversations from legitimate conversations. The research team is developing novel audio signal and natural language processing algorithms to detect emotional language that is unique to vishing conversations and novel natural language processing algorithms to detect requests for sensitive information. Collectively, these algorithms provide critical capabilities to detect vishing attacks in real-time and form the foundation of the real-time vishing attack warning system the research team is developing.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.