Capturing The Pitter-pat Of Fingerprints On Touchscreens

One Out Of Ten Times Or So That Is

Internet headlines are a never ending source of amusement, with the latest scare about capturing your fingerprints being no exception.  While many of the stories would have you believe that attackers can use a shotgun microphone to capture your fingerprints while you are typing, that is not exactly the case.  The PrintListener attack is roughly 27% effective at capturing partial fingerprints, which is not terribly useful for an attacker, and full fingerprints are captured less than 10% of the time.

The fingerprints are also not captured by typing, but through finger swipes on a touchscreen which are captured via the devices microphone.  This means you would need to make large swiping gestures on your phone while on an audio call with Discord, FaceTime or another chat app.  Someone with the PrintListener software that happened to be on that channel would have a chance at capturing the sounds of your fingerprints, but they wouldn’t get them if you are just typing.  You might want to avoid the swipe typing feature of your phone while on a call, or at least use a different finger from the one you use for biometrics. 

It is a worrying attack, but you don’t have to worry that your neighbour will be capturing your fingerprints from a distance while you are gaming.