Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Endpoint Security

10:00 AM
Larry Loeb
Larry Loeb
Larry Loeb

Mobile Phone Motion Sensors Found to Leak Tracking Data

A user's information can be accessed by an attacker in many ways, not just from a device's system software.

As Apple addressed its developers at this week's convention, it outlined all sorts of changes it was going to be making in its new software releases.

All of them shared the theme of user privacy. Apple is acting to differentiate itself from other device makers by presenting themselves as the most privacy conscious.

But a user's information can be accessed by an attacker in many ways, not just from a device's system software.

A recent paper outlined how a device can be fingerprinted (thereby giving a persistent link to its user) just from its hardware characteristics.

The paper came up with a proof of concept that utilized the M-series motion co-processors that are found in iPhones to generate a device fingerprint. These same kinds of sensors are on Android devices as well.

Access to these sensors does not require any special permissions, and the data can be accessed via both a native app that is installed on a device as well as by JavaScript when visiting a website on an iOS and Android device.

The researchers also found that no user interaction is required to leverage this kind of data access. An advertiser or other third-party can come up with this tracking data invisibly to the user.

It's well known that MEMS (Micro-Electro-Mechanical Systems) sensors are inaccurate in unique ways. Natural variation during the manufacture of embedded sensors means that the output of each sensor is unique.

iPhones as well as Google's Pixel 2 and 3 smartphones will try to compensate for this by using a calibration process that is applied to each sensor.

The strength of the calibration gives a value that inversely relates to the level of inaccuracy found in the sensor. Bingo, you have been fingerprinted to 67 bits of globally unique entropy.

Now, the researchers told Apple about this back in August of 2018. It responded to the problem with the fix inside iOS 12.2 in March 2019.

Apple masked the low-level sensor output by adding random noise to the analog-to-digital converter output. They also removed default access to motion sensors in Safari. They think that these steps will stop any exploitation of the effect in its tracks until iOS 13.

The authors say that they told Google in December 2018 about the situation. Android manufacturers usually don't do the calibration step because of cost, so those devices will not be vulnerable. But higher-end Android devices like the Galaxies do go the extra mile, and so are vulnerable to the privacy intrusion. Google has made no patch response as of yet. Maybe the idea of tracking devices seems good to the company.

Apple is acting in a way that shows them to be serious about privacy, as they told the developers. Compared to other areas, SensorID is a relatively small privacy issue. It was far more "potential" than "actual." However, mitigation -- which was not going to be simple -- could only be done by Apple. It was their responsibility. They did it. Unlike Google, who didn't.

If Apple keeps doing this kind of privacy stuff, "Sign In with Apple" is going to end up a trusted-by-the-users competitor in the sure-to-be-coming OAuth sweepstakes.

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 8/3/2020
Pen Testers Who Got Arrested Doing Their Jobs Tell All
Kelly Jackson Higgins, Executive Editor at Dark Reading,  8/5/2020
Researcher Finds New Office Macro Attacks for MacOS
Curtis Franklin Jr., Senior Editor at Dark Reading,  8/7/2020
Register for Dark Reading Newsletters
White Papers
Cartoon Contest
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Changing Face of Threat Intelligence
The Changing Face of Threat Intelligence
This special report takes a look at how enterprises are using threat intelligence, as well as emerging best practices for integrating threat intel into security operations and incident response. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
PUBLISHED: 2020-08-10
A function in Combodo iTop contains a vulnerability of Broken Access Control, which allows unauthorized attacker to inject command and disclose system information.
PUBLISHED: 2020-08-10
Combodo iTop does not validate inputted parameters, attackers can inject malicious commands and launch XSS attack.
PUBLISHED: 2020-08-10
Combodo iTop contains a stored Cross-site Scripting vulnerability, which can be attacked by uploading file with malicious script.
PUBLISHED: 2020-08-10
A security misconfiguration exists in Combodo iTop, which can expose sensitive information.
PUBLISHED: 2020-08-10
Combodo iTop contains a cross-site request forgery (CSRF) vulnerability, attackers can execute specific commands via malicious site request forgery.