Reputation has long been a crucial factor to establish trust and evaluate the character of others. In the field of cybersecurity, reputation is quantified and used as a metric to evaluate the risk an entity may pose to a network, similar to how financial credit scores are used to quantify the risk a person may pose to a lender. However, proposed methods are often presented as black boxes and lack scientific rigor, reproducibility, and validation. Additionally, most cybersecurity focused reputation metrics are intended for to quantifying the risk associated with domain names, IP ad-dresses, devices, or binaries and not for the users of a network. A user’s cyber reputation is defined as the most likely probability the user demonstrates a specific characteristic on the network, based on evidence.
I will discuss a case study on a large university network, where network traffic data is used as evidence to determine the likelihood a user becomes infected or remains uninfected on the network. A separate case study explores social media as an alternate source of data for evaluating user reputation. User-reported account compromise data is collected from Twitter and used to predict if a user will self-report compromise. This case study uncovers user cybersecurity experiences and victimization trends and emphasizes the feasibility of using social media to enhance understandings of users from a security perspective. As new threats to security, user privacy, and information integrity continue to manifest, the need for reputation systems and techniques to evaluate and validate online identities will continue to grow.
Michel Cukier is an associate professor of reliability engineering with a joint appointment in the Department of Mechanical Engineering at the University of Maryland, College Park. He is also the director for the Advanced Cybersecurity Experience for Students (ACES). His research covers dependability and security issues. His latest research focuses on the empirical quantification of cyber security. Dr. Cukier has published more than 70 papers in journals and refereed conference proceedings in those areas.