Conversation around the smartphone can be intercepted via a gyroscope

ByKārlis Dambrāns

A gyroscope for detecting the angle and angular velocity of an object is necessarily installed on a smartphone in recent years. Since it also plays a role of improving the accuracy of position information, when iOS · Android application uses gyroscope, you can use it without taking special permission. However, the latest gyroscope has become so high that it can sufficiently measure the acoustic signal around the smartphone, and the research team at Stanford University said, "Based on the super long wave information obtained from the gyroscope, the smartphone We analyze the contents of the conversation carried out around us to the level that can be recognized ", which made something ridiculous and successful.

Mobile Sensors Exploitation
http://crypto.stanford.edu/gyrophone/


Gyrophone: Recognizing Speech From Gyroscope Signals
(PDF file)http://crypto.stanford.edu/gyrophone/files/gyromic.pdf

You can understand the outline of the experiment by looking at the following movie.

Gyrophone: Recognizing Speech from Gyroscope Signals - YouTube


The gyroscope is installed on the modern smartphone to say "almost".


This gyroscope is a device for measuring angle and angular velocity.


On iOS and Android, when using this gyroscope there is no need to obtain authentication from users of smartphones.


Therefore, the research team seems to have started a study of whether it is possible to eavesdrop on the conversation around the smartphone using gyroscopes that can be used without user's permission.


When an application or web service uses a smartphone microphone, you need permission from the user. Therefore, we did not use the microphone at all, and it seems that we used only the information obtained from the gyroscope, that is, the data that the application and web service are now freely available.


As a result of this research, as well as information on the level at which individuals can be identified ... ...


social security numberYa


It seems that I could get up to the credit card number.


The research team of Stanford University is a defense company in IsraelRafaelIn cooperation with the research, the Android application invented in this research "Gyrophone(Downloadable directly from here) ", you will be able to collect sound vibration from the pressure plate in the gyroscope of the smartphone. The reason why you can record sound with a gyroscope is that Android is set to detect motion of 200Hz or 200 times per second in a gyrosensor, and this numerical value "200Hz" is a human voice It can cover mostly the frequency band of 80 Hz to 250 Hz.

The research team succeeded in reproducing "What is being talked about around the smartphone" from the sound recorded by the application. The sound that can be recorded via the gyroscope is like a slight wind noise for the human ear, but learn using machine learning, created by Yan Michalevsky of Stanford University and Gabi Nakibly of Rafael It has become possible to analyze sound accurately by the speech recognition program and to judge what kind of sound actually sounded.

ByTravis Isaacs

At the moment "Gyrophone" can record only a part of the conversation, and it is about one word such as numbers and "Oh" that you can get data at the same time. However, when the smartphone and the subject were placed in the same room and the subject was asked to speak appropriately in the room, it was possible to accurately identify each word of the subject's speech with a probability of 65% There was an 84% chance of hitting the speaker's gender.

Dan Boneh of the research team commented that "We are experts in the security field, not experts in speech recognition", and we have been using more appropriate speech recognition technology, experts engaged in the speech recognition part It will enable more accurate analysis as well. Although Android terminal and iOS terminal both have a gyroscope, iOS seems to restrict the gyroscope function to reading up to 100 Hz, and it is said that eavesdropping is more difficult than Android terminal is.

ByKārlis Dambrāns

In addition, although it is acoustic data that can be recorded from the gyroscope, it is possible to listen freely from the following page. "1" "2" "3" of the link destination seem to represent the axis of the gyroscope, and the data recorded on each axis is saved in each folder. Since the stored data is acoustic data before analysis, the sound of "hung" such as treble or bass is only slightly heard, but when I hear it, "If you can analyze conversations from such data ... ... It makes me feel like?

Dropbox - tidigits - small - wav
https://www.dropbox.com/sh/j88ci2m3tmmeter/AABaw3H28Kp-TW6s_xXv8BRna


further,From hereYou can record and download audio data that can be recorded by the gyroscope of your device.