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Secur."],"published-print":{"date-parts":[[2019,11,30]]},"abstract":"<jats:p>Voice-over-IP (VoIP) software are among the most widely spread and pervasive software, counting millions of monthly users. However, we argue that people ignore the drawbacks of transmitting information along with their voice, such as keystroke sounds\u2014as such sound can reveal what someone is typing on a keyboard.<\/jats:p>\n          <jats:p>\n            In this article, we present and assess a new keyboard acoustic eavesdropping attack that involves VoIP, called\n            <jats:italic>Skype &amp; Type<\/jats:italic>\n            (\n            <jats:italic>S&amp;T<\/jats:italic>\n            ). Unlike previous attacks,\n            <jats:italic>S&amp;T<\/jats:italic>\n            assumes a weak adversary model that is very practical in many real-world settings. Indeed,\n            <jats:italic>S&amp;T<\/jats:italic>\n            is very feasible, as it does not require (i) the attacker to be physically close to the victim (either in person or with a recording device) and (ii) precise profiling of the victim\u2019s typing style and keyboard; moreover, it can work with a very small amount of leaked keystrokes. We observe that leakage of keystrokes during a VoIP call is likely, as people often \u201cmulti-task\u201d during such calls. As expected, VoIP software acquires and faithfully transmits all sounds, including emanations of pressed keystrokes, which can include passwords and other sensitive information. We show that one very popular VoIP software (Skype) conveys enough audio information to reconstruct the victim\u2019s input\u2014keystrokes typed on the remote keyboard. Our results demonstrate that, given some knowledge on the victim\u2019s typing style and keyboard model, the attacker attains top-5 accuracy of 91.7% in guessing a random key pressed by the victim. This work extends previous results on\n            <jats:italic>S&amp;T<\/jats:italic>\n            , demonstrating that our attack is effective with many different recording devices (such as laptop microphones, headset microphones, and smartphones located in proximity of the target keyboard), diverse typing styles and speed, and is particularly threatening when the victim is typing in a known language.\n          <\/jats:p>","DOI":"10.1145\/3365366","type":"journal-article","created":{"date-parts":[[2019,12,9]],"date-time":"2019-12-09T13:35:27Z","timestamp":1575898527000},"page":"1-34","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":16,"title":["Skype &amp; Type"],"prefix":"10.1145","volume":"22","author":[{"given":"Stefano","family":"Cecconello","sequence":"first","affiliation":[{"name":"University of Padua, Italy"}]},{"given":"Alberto","family":"Compagno","sequence":"additional","affiliation":[{"name":"Cisco Systems, Issy-les-Moulineaux, France"}]},{"given":"Mauro","family":"Conti","sequence":"additional","affiliation":[{"name":"University of Padua, Italy"}]},{"given":"Daniele","family":"Lain","sequence":"additional","affiliation":[{"name":"ETH Zurich, Zurich, Switzerland"}]},{"given":"Gene","family":"Tsudik","sequence":"additional","affiliation":[{"name":"University of California, Irvine, USA"}]}],"member":"320","published-online":{"date-parts":[[2019,12,6]]},"reference":[{"key":"e_1_2_1_1_1","unstructured":"[n.d.]. Opus Codec Support. Retrieved from https:\/\/wiki.xiph.org\/OpuSupport.  [n.d.]. Opus Codec Support. Retrieved from https:\/\/wiki.xiph.org\/OpuSupport."},{"key":"e_1_2_1_2_1","unstructured":"[n.d.]. Oxford Dictionary. Which Letters in the Alphabet Are Used Most Often. Retrieved from http:\/\/www.oxforddictionaries.com\/words\/which-letters-are-used-most.  [n.d.]. Oxford Dictionary. Which Letters in the Alphabet Are Used Most Often. Retrieved from http:\/\/www.oxforddictionaries.com\/words\/which-letters-are-used-most."},{"key":"e_1_2_1_3_1","unstructured":"[n.d.]. 2015: Skype\u2019s Year in Review. Retrieved from http:\/\/blogs.skype.com\/2015\/12\/17\/2015-skypes-year-in-review\/.  [n.d.]. 2015: Skype\u2019s Year in Review. Retrieved from http:\/\/blogs.skype.com\/2015\/12\/17\/2015-skypes-year-in-review\/."},{"key":"e_1_2_1_4_1","unstructured":"[n.d.]. Over 1 billion Skype Mobile Downloads. Retrieved from http:\/\/blogs.skype.com\/2016\/04\/28\/over-1-billion-skype-mobile-downloads-thank-you\/.  [n.d.]. Over 1 billion Skype Mobile Downloads. Retrieved from http:\/\/blogs.skype.com\/2016\/04\/28\/over-1-billion-skype-mobile-downloads-thank-you\/."},{"key":"e_1_2_1_5_1","unstructured":"[n.d.]. Microsoft BUILD 2016 Keynote. Retrieved from https:\/\/channel9.msdn.com\/Events\/Build\/2016\/KEY01.  [n.d.]. Microsoft BUILD 2016 Keynote. Retrieved from https:\/\/channel9.msdn.com\/Events\/Build\/2016\/KEY01."},{"key":"e_1_2_1_6_1","doi-asserted-by":"publisher","DOI":"10.1145\/2789168.2790109"},{"key":"e_1_2_1_7_1","volume-title":"Proceedings of the ACM Conference on Data and Application Security and Privacy (CODASPY\u201918)","author":"Abhishek Anand S.","year":"2018","unstructured":"S. Abhishek Anand and Nitesh Saxena . 2018 . Keyboard emanations in remote voice calls: Password leakage and noise (less) masking defenses . 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