Provably Improving Election Verifiability in Belenios

Belenios is an online voting system that provides a strong notion of election verifiability, where no single party has to be trusted, and security holds as soon either the registrar or server honest. It was formally proved secure, making assumption further ballots are cast on bulletin board after voters verified their ballots. In practice, however, revoting allowed can verify anytime. This gap between formal proofs use in practice leaves open space for attacks, been shown recently. this paper we make two simple additions prove new version satisfies expected verifiability properties. Our automatically performed with Tamarin prover, under vote at most four times.