It was found that the personal terminal can be specified and tracked by the acceleration sensor of the smartphone, and there is also a danger of being abused by advertisement

ByKit

A method of distributing targeted Internet advertisements by estimating interests based on the user's action historyBehavioral targeting advertisementIt is called. Researchers at Stanford University point out the dangers of smart "acceleration sensor" being exploited for this targeted advertisement.

Stanford researchers discover 'alarming' method for phone tracking, fingerprinting through sensor flaws | The Technology Chronicles | an SFGate.com blog
http://blog.sfgate.com/techchron/2013/10/10/stanford-researchers-discover-alarming-method-for-phone-tracking-fingerprinting-through-sensor-flaws/

As beforeCookieAlthough it was able to identify individual user's ID by identifying each user's identity and use it for advertisement strategy by monitoring online behavior, the latest trend of user's behavior tracking is that the smartphone's acceleration sensor is on the web It seems to be a method to utilize the data to leave.

Hristo Bojinov of Stanford University discovered that each terminal can be identified by a simple method of analyzing the data provided by the acceleration sensor of the smartphone to the web page. According to Bojinov, using this method it is possible to track that terminal on the web.

Although the acceleration sensor is now equipped as a standard function of the smartphone, the accuracy of the sensor has slight deviation (error) for each terminal, and since this error is a value unique to each terminal, It acts like a "fingerprint" on the terminal. In other words, by examining the fingerprint of the acceleration sensor, it is possible to distinguish individual terminals.

This is a graph that distributes numerical values ​​of error of acceleration sensors of 16 terminals tested.


Bojinov says "It is possible to collect fingerprint data of this acceleration sensor by introducing a little script on any website", and in fact it is possible to use the acceleration sensor by the following method It is getting.

I tried the JavaScript acceleration sensor API which was implemented from iOS 4.2 | ke-tai.org - Infinite loop


I tried acquiring the iPhone acceleration sensor with JavaScript | CYBER BALLAD


[Tsu] Sample to obtain inclination of Android 3.0 terminal with JavaScript Device Orientation (2011-06-13)


Coboral.net »Use Android Accelerometer in Browser


In addition, while it is possible for the user to set up measures to prevent this against tracking of cookies, specific information collection applications, etc., the function of collecting acceleration fingerprint data charged on the web is sensed by the user Since it is impossible to do so, it is a problem that it is impossible to take measures. Bojinov said it is uncertain whether someone is already using this technique, "If it is not even if anyone is still exploring the possibility of this acceleration sensor data, that's amazing." I will talk.

Furthermore, Bojinov's research group exploits the same as the acceleration data because it has a characteristic for each terminal even when the value of the frequency sensed by the microphone of the smartphone sounds when sounds of various musical scales are played I also found out what I can do.

In the lower 3D graph, each color represents the response of the scale frequency of 16 models. From the experimental results done three times, you can see that the frequency data has exactly the same shape.


In addition to the method discovered by the researchers of Stanford this time, there are many other ways to identify the terminal, so as long as the behavior tracking of the user is extremely effective for online advertisement and it is money, a new technology And the birth of laws and regulations and the development of methods to try to avoid this seems to continue as a milestone in the future. According to the New York Times,Google is seeking to adopt new user tracking methods to replace cookies in advertisements, And we are doing.