Google is investigating whether it should take measures against identifying individual smartphones on the basis of calibration data from sensors. That’s now possible on the Pixel 2 and Pixel 3, researchers say.
Graphical representation of data from two iPhone Xs
Google has known about the problem with its smartphones since December 10 last year, but has not yet taken action, notes the paper by some British researchers. The Pixel 2 and 3 have some files on the devices that contain calibration data for the accelerometer. Due to the manufacturing process of that sensor, deviations occur, which manufacturers can rectify with factory calibration.
Websites and apps can read sensor data without users’ consent and thereby recognize individual users without cookies or other fingerprinting methods. Sites can use this to, for example, show targeted advertisements. The researchers from the British University of Cambridge and the company Polymath have also tested other Android smartphones, but they were not identified through the calibration data of sensors. They do not name types, but the researchers use a Samsung Galaxy S8 elsewhere in the study.
The researchers mainly focused on iPhones. Apple has known about this problem since August last year and has solved it in iOS 12.2 in response to the report from British researchers. The researchers have named their method of identifying devices SensorID. Being able to recognize smartphones by calibration data has been a known technique for years. American researchers have already found ways to do this on the Google Nexus S smartphone from 2010. Many sites on the Internet now use motion sensor detection to recognize users.