Abstract
Fallback authentication refers to a chain of alternative authentication schemes that are is-sued if the main authentication method fails such as the provision of information on cre-dentials and security challenge questions. The user authentication domain includes a num-ber of contribution efforts to increase the usability and security of fallback authentication systems. The aim of this study is to collect the existing knowledge on fallback authentica-tion techniques and related issues through a systematic literature review. In addition, this paper explores the frameworks that can be used to compare fallback authentication tech-niques according to different criteria. A total of 70 articles were reviewed, different fallback authentication techniques have been found and 9 frameworks were discussed. The lack of frameworks regarding the comparison of fallback authentication schemes is observed. Finally, this study discusses the research gaps and recommendations that are critical to fallback authentication. (c) 2021 Elsevier Ltd. All rights reserved.