Was This You? Investigating the Design Considerations for Suspicious Login Notifications

—Many online platforms monitor the account login activities of their users to detect unauthorized login attempts. Upon detecting anomalous activity, these platforms send suspicious login notifications to their users. These notifications serve to inform users about the login activity in sufficient detail for them to ascertain its legitimacy and take remedial actions if necessary. Despite the prevalence of these notifications, limited research has explored how users engage with them and how they can be effectively designed. In this paper, we examine user engagement with email-based suspicious login notifications, focusing on real-world practices. We collect and analyze notifications currently in use to establish an empirical foundation for common design elements. We focus our study on designs used by online platforms rather than exploring all possible design options. Thus, these design options are likely supported by real-world online platforms based on the login data they can realistically provide. Then, we investigate how these design elements influence users to read the notification, validate its authenticity, diagnose the login attempt, and determine appropriate remedial steps. By conducting online semi-structured interviews with 20 US-based participants, we investigate their past experiences and present them with design elements employed by top online platforms to identify what design elements work best. Our findings highlight the practical design options that enhance users’ understanding and engagement, providing recommendations for deploying effective notifications and identifying future directions for the security community.