A rigorous security analysis of a decentralized electronic voting protocol in the universal composability framework

Designing an efficient and secure electronic voting (e-voting) protocol without the presence of trusted authorities, known as decentralized voting protocols, is one of the most interesting and challenging problems in cryptography. In these protocols the outcome of the protocol is computed by voters collaborating with each other. We provide a rigorous proof of security of a decentralized e-voting protocol proposed by Khader et al. in the Universal Composability (UC) Framework. This protocol is the state-of-the-art decentralized e-voting protocol in terms of efficiency and security, whose security has only been justified against a set of desired properties required in e-voting protocols. For security analysis of e-voting protocols, intuitive proof is not enough and we require a comprehensive approach that provides provable security. Our result settles this concern. (C) 2018 Elsevier Ltd. All rights reserved.