Implementing an Audio Side Channel for Paper Voting
In the ongoing debate between the proponents of electronic and paper voting, a frequently used argument is that electronic voting is susceptible to electronic attacks, and those are less detectable by a human than physical ones. This paper contributes to the research of electronic attacks against paper voting by building a proof-of-concept classifier for audio samples recorded while writing numbers. Such a classifier can be used to break the privacy, for example, in case of preferential voting ballot sheets, or voting systems where the voter must fill in the candidate number. We estimate the quality of the classifier and discuss its implications to the physical security measures of polling stations and ballot design.
The research leading to these results has received funding from the Estonian Research Council under Institutional Research Grant IUT27-1 and the European Regional Development Fund through the Estonian Centre of Excellence in ICT Research (EXCITE) and the grant number EU48684. We would also like to thank all the volunteers contributing the writing samples used in this research, anonymous reviewers for their comments, and our shepherd Dr. Marco Prandini for helpful and thought-provoking discussions.
- 1.Kohaliku omavalitsuse volikogu valimiste käsiraamat (2017). https://www.valimised.ee/sites/default/files/uploads/kov2017/KOV2017_kasiraamat_web.pdf
- 2.Adida, B., Neff, C.A.: Ballot casting assurance. In: USENIX Electronic Voting Technology Workshop (2006)Google Scholar
- 3.Calandrino, J.A., Clarkson, W., Felten, E.W.: Some consequences of paper fingerprinting for elections. In: EVT/WOTE (2009)Google Scholar
- 5.Gonggrijp, R., Hengeveld, W.J.: Studying the Nedap/Groenendaal ES3B voting computer: a computer security perspective. In: Proceedings of the USENIX Workshop on Accurate Electronic Voting Technology. USENIX Association, Berkeley (2007)Google Scholar
- 8.Loeber, L.: E-voting in the Netherlands; from general acceptance to general doubt in two years. In: 3rd International Conference on Electronic Voting. LNI, GI-Edition, vol. 131, pp. 21–30 (2008)Google Scholar
- 11.Rivest, R.L.: The ThreeBallot Voting System (2006). http://people.csail.mit.edu/rivest/Rivest-TheThreeBallotVotingSystem.pdf
- 12.Verhelst, W., Roelands, M.: An overlap-add technique based on waveform similarity (WSOLA) for high quality time-scale modification of speech. In: 1993 IEEE International Conference on Acoustics, Speech, and Signal Processing, vol. 2, pp. 554–557, April 1993Google Scholar
- 13.Yu, T., Jin, H., Nahrstedt, K.: Audio based eavesdropping of handwriting via mobile devices. In: Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing, pp. 463–473. ACM (2016)Google Scholar