key: 2016-attacking-eligibility-in-Helios
type: article
title: Exploiting re-voting in the Helios election system
authors:
  - Maxime Meyer
  - Ben Smyth
year: 2019
journal: Information Processing Letters
volume: "143"
pages: 14--19
doi: 10.1016/j.ipl.2018.11.001
description: This paper presents an attack against the Helios election system that violates eligibility.
keywords: >-
  voting, Helios, eligibility, non-reusability, attack, verifiability, election system, electronic
  voting, e-voting
abstract: >-
  Election systems must ensure that representatives are chosen by voters. Moreover, each voter
  should have equal influence. Traditionally, this has been achieved by permitting voters to cast at
  most one ballot. More recently, this has been achieved by tallying the last ballot cast by each
  voter. We show this is not achieved by the Helios election system, because an adversary can cause
  a ballot other than a voter's last to be tallied. Moreover, we show how the adversary can choose
  the contents of such a ballot, thus the adversary can unduly influence the selection of
  representatives.
video:
  youtube: Jm4XacGU-44
  text: Video demonstration
extra: "<h2>Video demonstration</h2>\n\t\t<p>Our video demonstrating our attack is available on YouTube.</p>\n"
links:
  - file: Smyth16-attacking-eligibility-in-Helios.pdf
    text: Draft
    alt:
      url: http://arxiv.org/abs/1612.04099
      text: arXiv version
  - url: https://doi.org/10.1016/j.ipl.2018.11.001
    text: Official version