How to prove the validity of a complex ballot encryption to the voter and the public

in Journal of Information Security and Applications (2014)

One crucial aspect of any verifiable electronic voting system that uses encryption is the proof that the vote encryption is well-formed, i.e. the proof that the vote encryption encrypts a valid vote ... [more ▼]

One crucial aspect of any verifiable electronic voting system that uses encryption is the proof that the vote encryption is well-formed, i.e. the proof that the vote encryption encrypts a valid vote accordingly to the race specification. It makes no sense accepting an encrypted vote if, at the end of the election, the vote cannot be included in the tally because it is badly formed. Proving the validity of a complex vote encryption, without revealing the vote, is a hard problem. This paper first contribution addresses exactly that problem and provides a set of new constructions to create a vote encryption and the corresponding public proof of validity for several types of complex ballots ([kmin,kmax]-out-of-n approval, weighted and ranked ballots). The second contribution is a technique that allows to create a single, constant size, verification code for a ballot containing one or several races of any mix of the race types considered. With this single verification code the voter can verify that her vote was cast-as-intended. Moreover, our constructions can be tuned for either mix net or homomorphic tallying and support both types of tallying in the same multi-race ballot. [less ▲]

EVIV: An end-to-end verifiable Internet voting system

in Computers and Security (2013), 32(0), 170-191

Traditionally, a country’s electoral system requires the voter to vote at a specific day and place, which conflicts with the mobility usually seen in modern live styles. Thus, the widespread of Internet ... [more ▼]

Traditionally, a country’s electoral system requires the voter to vote at a specific day and place, which conflicts with the mobility usually seen in modern live styles. Thus, the widespread of Internet (mobile) broadband access can be seen as an opportunity to deal with this mobility problem, i.e. the adoption of an Internet voting system can make the live of voter’s much more convenient; however, a widespread Internet voting systems adoption relies on the ability to develop trustworthy systems, i.e. systems that are verifiable and preserve the voter’s privacy. Building such a system is still an open research problem. Our contribution is a new Internet voting system: EVIV, a highly sound End-to-end Verifiable Internet Voting system, which offers full voter’s mobility and preserves the voter’s privacy from the vote casting PC even if the voter votes from a public PC, such as a PC at a cybercafe´ or at a public library. Additionally, EVIV has private vote verificationmechanisms, in which the voter just has to perform a simple match of two small strings (4-5 alphanumeric characters), that detect and protect against vote manipulations both at the insecure vote client platform and at the election server side. [less ▲]

Improving Remote Voting Security with CodeVoting

in Chaum, David; Jakobsson, Markus; Rivest, Ronaldl (Eds.) et al Towards Trustworthy Elections (2010)

One of the major problems that prevents the spread of elections with the possibility of remote voting over electronic networks, also called Internet Voting, is the use of unreliable client platforms, such ... [more ▼]

One of the major problems that prevents the spread of elections with the possibility of remote voting over electronic networks, also called Internet Voting, is the use of unreliable client platforms, such as the voter’s computer and the Internet infrastructure connecting it to the election server. A computer connected to the Internet is exposed to viruses, worms, Trojans, spyware, malware and other threats that can compromise the election’s integrity. For instance, it is possible to write a virus that changes the voter’s vote to a predetermined vote on election’s day. Another possible attack is the creation of a fake election web site where the voter uses a malicious vote program on the web site that manipulates the voter’s vote (phishing/pharming attack). Such attacks may not disturb the election protocol, therefore can remain undetected in the eyes of the election auditors. We propose the use of CodeVoting to overcome insecurity of the client platform. CodeVoting consists in creating a secure communication channel to communicate the voter’s vote between the voter and a trusted component attached to the voter’s computer. Consequently, no one controlling the voter’s computer can change the his/her’s vote. The trusted component can then process the vote according to a cryptographic voting protocol to enable cryptographic verification at the server’s side. [less ▲]

CodeVoting Protection Against Automatic Vote Manipulation in an Uncontrolled Environment

in Alkassar, Ammar; Volkamer, Melanie (Eds.) E-Voting and Identity (2007)

One of the major problems that prevent the widespread of Internet voting is the vulnerability of the voter’s computer. A computer connected to the Internet is exposed to virus, worms, spyware, malware and ... [more ▼]

One of the major problems that prevent the widespread of Internet voting is the vulnerability of the voter’s computer. A computer connected to the Internet is exposed to virus, worms, spyware, malware and other threats that can endanger the election’s integrity. For instance, it is possible to write a virus that changes the voter’s vote to one predetermined vote on election’s day. It is possible to write such a virus so that the voter would not notice anything wrong with the voting application. This attack is very dangerous because it may pass undetected. To prevent such attack it is necessary to prevent automatic vote manipulation at voter’s computer. Here we present CodeVoting, a technique to create a secure communication channel to a smart card that prevents vote manipulation by the voter’s PC, while at the same time allows the use of any cryptographic voting protocol to protect the election’s integrity at the server side of the voting application. [less ▲]