More Than Just Good Passwords? A Study on Usability and Security Perceptions of Risk-based Authentication

TL;DR

This study evaluates user perceptions of risk-based authentication (RBA), finding it more usable than 2FA and perceived as more secure than passwords, with insights to improve RBA adoption.

Contribution

First comprehensive user perception study of RBA, comparing it to 2FA and password-only methods, with practical usability recommendations.

Findings

RBA is considered more usable than 2FA variants.

Users perceive RBA as more secure than passwords.

Identified usability problems and suggested mitigations.

Abstract

Risk-based Authentication (RBA) is an adaptive security measure to strengthen password-based authentication. RBA monitors additional features during login, and when observed feature values differ significantly from previously seen ones, users have to provide additional authentication factors such as a verification code. RBA has the potential to offer more usable authentication, but the usability and the security perceptions of RBA are not studied well. We present the results of a between-group lab study (n=65) to evaluate usability and security perceptions of two RBA variants, one 2FA variant, and password-only authentication. Our study shows with significant results that RBA is considered to be more usable than the studied 2FA variants, while it is perceived as more secure than password-only authentication in general and comparably secure to 2FA in a variety of application types. We also observed RBA usability problems and provide recommendations for mitigation. Our contribution provides a first deeper understanding of the users' perception of RBA and helps to improve RBA implementations for a broader user acceptance.