Researchers have created a program called Skype&Type for listening on keystrokes typed during a Skype call by learning what frequency matches with specific keys on a laptop. Most recently, one of the researchers involved in the project, Daniele Lain presented this research at the Black Hat USA 2017 conference. This was also reported and tested a bit earlier in the month by Forbes. Though, it's still an early prototype, and not perfect, still the accuracy of the program can be astounding in most cases, reaching up to 90% accuracy in certain cases.
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