Hack smartphone password via touch screen sound

According to Business Insider, microphones in handheld devices can be used by malware to steal users' passwords and PINs.

According to researchers at Cambridge University in England and Linköping University in Sweden, this stealing technique is based on machine learning technology. Test results showed that malicious software can correctly guess more than half of the four-digit PIN used on Android tablets.

This shows that sound on smartphones and tablets can become the new target of attacks.

How does an attack technique based on sound waves and microphones take place?

Users will create sound waves when they touch the screen of smartphones and tablets. Currently, most modern handhelds have many micrometers to use for many different activities such as voice calls, for voice recording, voice memo .

Researchers have created a software that can be based on where the sound is coming from on the screen, the difference can be measured by the fraction of seconds, to give the predicted key that the user typed.

After 10 attempts, the system can correctly guess 73% of four-digit passwords. With a password of between seven and 13 characters long, it can determine exactly 30% after 20 attempts.

To exploit the vulnerability researchers found, hackers had to install malware on the phone and get permission for the software to access the device's microphone from the user.

In fact, this is very unlikely because most current operating systems do not allow applications that use the device's microphone unless the user agrees.