15 experiments to do with your mobile

'Zoom snooping', the technique that allows us to know what we have typed during a video call by our shoulder movement

You have probably heard of 'Zoom bombing', the practice of breaking into other people's video calls, usually with the aim of scandalizing the participants. But you may not have heard of 'Zoom snooping', despite the fact that its consequences for Zoom users (and other similar applications) can be much worse.

The 'zoom snooping' consists of use the images of a participant in a video call to extract personal information from the participant, including their passwords. But how is that? Maybe it's because people leave post-its with sensitive data in view while in front of the webcam?

It looks like science fiction

The truth is that no, because 'zoom snooping' is something much more complex and subtle: the movements of our shoulders are monitored and analyzed while we write during video calls, in order to deduce what we are writing. For practical purposes, not much different from being the victim of a keylogger.

Yes, this week a study by the University of Texas (PDF) was published showing that this is possible: researchers have been able to infer if the very slight movements of our shoulders (and arms) mean that we have moved our hands up, down, right or left.

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Thus, they can establish equivalences between these movements and keystrokes on a QWERTY keyboard (or any other keyboard configuration, for that matter), then reconstructing the typed words.

In a controlled environment (that is, previously knowing the model of chairs, keyboards and webcam used), this technique had an accuracy rate of 75%, although it fell to 20% in 'uncontrolled' environments. The use of long or short sleeves also influences, and that the monitored user has shoulder length hair It can prevent you from falling victim to 'zoom snooping'.

The technologist Bruce Schneier has affirmed, as a result of the publication of the study that although "its precision is not great, what it allows to do is impressive".


The truth is that this technique It comes to join a long technique of espionage methods that border on science fiction, like using the accelerometer and gyroscope of smartphones as a way to deduce your PIN, and the analysis of the microvibrations of a bag of chips to know what is being said in the immediate vicinity.

So, you already know how to make it difficult for cyber attackersKeep an eye on who you share video calls with, avoid typing in relevant personal information while participating in one, and ... grow your hair long.

Via | TechExplore