Borisov identifies "motion sensor fingerprinting" smartphone privacy threat

Your smartphone can already detect your movement. It can sense if you’ve rotated it to take a landscape photo and how you’ve tilted it to play a game. But could this same technology be exploited by advertisers? ECE ILLINOIS Professor Nikita Borisov said it is possible with motion sensor fingerprinting.

Online technology magazine Motherboard featured his recent research about a possible method to track smartphone users by analyzing the device's unique motion sensing data. Every smartphone’s unique hardware settings, user specifications, and other personalized information can be used to assemble a unique profile or “fingerprint,” and advertisers can use that customized profile to track a smartphone's web activities - a technique called “motion sensor fingerprinting.”

“We can conclude that motion sensor fingerprinting is a realistic threat to mobile users’ privacy,” Borisov's team wrote in the paper. Borisov explained that conventional workarounds like private browsing and clearing cookies would no longer be effective against this new method of mobile tracking, because it relies upon data collected about the physical device itself.

The team also explored two counter-measures and how they impacted the user experience in web applications. Both a previously proposed obfuscation technique and a newly developed quantization technique were able to drastically reduce fingerprinting accuracy without significantly impacting the utility of the sensors in web applications in a user study.

"Smartphone Fingerprinting via Motion Sensors: Analyzing Feasibility at Large-Scale and Studying Real Usage Patterns" was co-written by Borisov, computer science PhD candidate Anupam Das, computer engineering junior Edward Chou, and Hong Kong University of Science and Technology computer science PhD candidate Muhamad Haris Mughees.