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Smartphone ambient light sensors are used to automatically adjust screen brightness, but researchers reveal that they can be turned into cameras and used to secretly film unsuspecting victims and their surroundings.

Researchers at MIT’s Computer Science and Artificial Intelligence Laboratory proposed a computational imaging algorithm that allowed the recovery of an image of the environment from the screen’s perspective.

According to Cybernews, ambient light sensors are tiny devices deployed in almost all portable devices and screens that surround us in our daily lives. As such, the authors highlight a privacy threat that affects a comprehensive class of devices and has been overlooked so far.

The study suggests that ambient light sensors could intercept various user gestures like swiping and sliding, and capture how users interact with their phones while watching videos. The main point of the study was to disprove the belief that ambient light sensors can’t reveal any meaningful private information to attackers, so apps should be able to freely request access to them.

Yang Liu, a PhD at the MIT Electrical Engineering & Computer Science Department explains that ambient light sensors capture what we’re doing without permission and can pose privacy risks to users when combined with a display screen.

One suggestion by the researchers was that software makers tighten permissions and reduce the precision and speed of the sensors. Another way to combat the security issue would be to allow users the same control they have over app permissions to access their camera or microphone. A suggestion made for future devices was that they have the ambient light sensors facing away from the user, like to the side of the device for example.

In conclusion, cybersecurity researchers are finding more and more innovative ways to spy on users. An example of this is our article regarding an AI algorithm that can know what you are typing by the sounds of your keyboard.