Thu. Jun 4th, 2020

Research: the device’s microphone can reveal the content you type on your phone

2 min read

With the advancement of technology, hackers can quickly steal the user’s typing on the device by analyzing the sound of the device keyboard. Researchers at the UK’s University of Cambridge and Sweden’s Linköping University have found that the input password can be cracked by tapping the sound waves generated by the touch screen of the smartphone. Sound waves are generated when the user enters text on the touch screen. The device microphone can record sound waves, and researchers can associate sound waves with the keys that the user enters.

According to the study, a spy application, a hacker, can decode what the user entered. Researchers say that using this attack can successfully recover PIN codes, individual letters, and entire words. The spyware may be installed by the victim himself, it may be installed by someone else, or it may be that the attacker installed the software beforehand and then gave the device to the victim. Many applications have microphone access, and most people blindly accept this permission requirement.

Researchers have written a machine learning algorithm that detects and analyzes the sound waves of a particular button. On smartphones, as a result, to correctly calculate 27 out of 45 passwords typed on a smartphone, and 19 out of 27 passwords typed on a tablet.

The researchers found that the device’s microphone can recover this sound wave and hear the finger’s touch, which is caused by tapping different screen positions. Therefore, by recording audio through the built-in microphone, a malicious application can infer text content as the user enters text.