Skip to main content

Your smartphone’s gyroscope can be turned into an eavesdropping hacker’s microphone

Smartphone microphone gyroscope
Image used with permission by copyright holder
If you own a smartphone, chances are it has a gyroscope – and chances also are that gyroscope can be used (without special permissions) as a microphone to listen in on your private conversations. This is the startling finding from two researchers from Stanford University’s Computer Science Department and one researcher from Rafael Advanced Defense Systems, who authored a paper titled “Gyrophone: Recognizing Speech From Gyroscope Signals.”

According to the paper, microelectromechanical systems (MEMS) gyroscopes found in modern smartphones are sensitive enough to pick up acoustic signals. While these raw signals aren’t enough to glean useful information from, the researchers used signal processing and algorithms to identify the correct speaker from a set of 10 possible speakers with a 50 percent success rate.

Related: Who needs malware? I could have wrecked this kid’s life with a notepad

Using a Nexus 4 and a Galaxy S3, they were also able to successfully recognize simple speech up to 65 percent of the time in speaker-dependent cases and up to 26 percent of the time in speaker-independent cases. The gyroscopes in these phones were also used to correctly identify a speaker’s gender up to 84 percent of the time.

“Since iOS and Android require no special permissions to access the gyro, our results show that apps and active web content that cannot access the microphone can nevertheless eavesdrop on speech in the vicinity of the phone,” according to the paper.

The researchers also offer two suggestions for defending against gyroscope-based eavesdropping: apply low-pass filtering to raw samples provided by the gyroscope, or apply a form of acoustic masking around the gyroscope itself or on a smartphone’s case.

“A general conclusion we suggest following this work is that access to all sensors should be controlled by the permissions framework, possibly differentiating between low and high sampling rates,” according to the researchers.

The paper will be presented at the 23rd USENIX Security Symposium in San Diego on Friday, Aug. 22.

Those interested in downloading an Android application that can be used for sampling a phone’s gyroscope can head to the Stanford Security Research page dedicated to the paper.

Editors' Recommendations

Jason Hahn
Jason Hahn is a part-time freelance writer based in New Jersey. He earned his master's degree in journalism at Northwestern…
Parents unite in smartphone ban for children
Children using a smartphone.

Parents in a town in Ireland have come together in a bid to remove the temptations of smartphones from their children’s daily life, the Guardian reported.

Concerned about the adverse effect that social media might be having on their offspring, parents in Greystones -- a community of around 18,000 located 14 miles south of Dublin -- agreed to launch a town-wide no-smartphone rule that means their children will only be able to get a handset once they reach secondary school at around the age of 13.

Read more
Want to turn your iPhone into a Galaxy S23? This app is for you
OneUI TryGalaxy view

The best kind of marketing is the one that happens in the hands of an interested person who just might be your next customer. Samsung certainly thinks that way and is trying its best, not just because it’s a sound strategy, but also owing to the fact that arch-rival Apple has mastered the art with its meticulously imagined store experience.

Samsung’s latest ploy is a web app designed for iPhones that will give you a taste of its One UI 5.1 software that runs on its Galaxy S23 series phones. Actually, scratch that. The company is welcoming you to “the other side” by letting you experience its heavily customized take on Android and find out for yourself if it can surpass iOS for you. The solution is called Try Galaxy.
Try Galaxy makes your iPhone a Samsung phone

Read more
The 15 most important smartphones that changed the world forever
Huawei P30 Pro and P30

If there’s any piece of technology that has made a significant impact on the lives of everyone, it’s the cellular phone —  specifically, the smartphone. It’s literally a tiny computer that fits into your pocket, and brings a plethora of information, entertainment, and lets you capture visual memories or be productive wherever you go. Pretty much everyone has a smartphone these days, for better or for worse.

But have you ever thought about which smartphones have been the most important and influential ones that shaped the rest of the industry? Let’s take a look at what we consider to be the most important smartphones of all time.
iPhone (2007)

Read more