Implementing an Audio Side Channel for Paper Voting

  • Kristjan Krips
  • Jan WillemsonEmail author
  • Sebastian Värv
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11143)


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. 1.
    Kohaliku omavalitsuse volikogu valimiste käsiraamat (2017).
  2. 2.
    Adida, B., Neff, C.A.: Ballot casting assurance. In: USENIX Electronic Voting Technology Workshop (2006)Google Scholar
  3. 3.
    Calandrino, J.A., Clarkson, W., Felten, E.W.: Some consequences of paper fingerprinting for elections. In: EVT/WOTE (2009)Google Scholar
  4. 4.
    Cover, T.M., Hart, P.J.: Nearest neighbor pattern classification. IEEE Trans. Inf. Theor. 13(1), 21–27 (1976)CrossRefGoogle Scholar
  5. 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
  6. 6.
    Jacobs, B., Pieters, W.: Electronic voting in the Netherlands: from early adoption to early abolishment. In: Aldini, A., Barthe, G., Gorrieri, R. (eds.) FOSAD 2007-2009. LNCS, vol. 5705, pp. 121–144. Springer, Heidelberg (2009). Scholar
  7. 7.
    Lance, G.N., Williams, W.T.: Computer programs for hierarchical polythetic classification (similarity analyses). Comput. J. 9(1), 60–64 (1966)CrossRefGoogle Scholar
  8. 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
  9. 9.
    Moran, T., Naor, M.: Receipt-free universally-verifiable voting with everlasting privacy. In: Dwork, C. (ed.) CRYPTO 2006. LNCS, vol. 4117, pp. 373–392. Springer, Heidelberg (2006). Scholar
  10. 10.
    Pedregosa, F., et al.: Scikit-learn: machine learning in Python. J. Mach. Learn. Res. 12, 2825–2830 (2011)MathSciNetzbMATHGoogle Scholar
  11. 11.
    Rivest, R.L.: The ThreeBallot Voting System (2006).
  12. 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. 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

Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Kristjan Krips
    • 1
  • Jan Willemson
    • 1
    • 2
    Email author
  • Sebastian Värv
    • 1
  1. 1.Cybernetica ASTartuEstonia
  2. 2.Software Technology and Applications Competence CenterTartuEstonia

Personalised recommendations