NordVPN transfers data to tracking service
kuketz-blog.de
kuketz-blog.de
the nordvpn app for android is sending device data to multiple trackers.
It contains all the normal things you probably expect, screen size, manufacturer, uuids for advertising etc but also some strangely specific stuff.
This includes sensor data (Gyroscope, Accelerometer, etc)
from the json sent to "AppsFlyer":
sensors":[{"sT":4,"sV":"BOSCH","sVE":[0.015487671,0.022598267,-0.013870239],"sVS":[-0.061203003,-0.059432983,0.04260254],"sN":"BMI160 Gyroscope -Wakeup Secondary"},{"sT":1,"sV":"BOSCH","sVE":[0.6355438,6.844879,7.2422333],"sVS":[0.1184082,6.7634735,7.1632233],"sN":"BMI160 Accelerometer -Wakeup Secondary"},{"sT":4,"sV":"BOSCH","sVE":[0.015487671,0.022598267,-0.013870239],"sVS":[-0.061203003,-0.059432983,0.04260254],"sN":"BMI160 Gyroscope"},{"sT":2,"sV":"Yamaha","sVE":[46.717834,-18.313599,-34.529114],"sVS":[46.717834,-20.56427,-33.029175],"sN":"YAS537 Magnetometer"},{"sT":2,"sV":"Yamaha","sVE":[46.717834,-18.313599,-34.529114],"sVS":[46.717834,-20.56427,-33.029175],"sN":"YAS537 Magnetometer -Wakeup Secondary"},{"sT":1,"sV":"BOSCH","sVE":[0.6355438,6.844879,7.2422333],"sVS":[0.1184082,6.7634735,7.1632233],"sN":"BMI160 Accelerometer"}I can see how it would be useful for invalidating data in analytics, seems like a bad choice of partner for an app promoting privacy though.
As an anti-analysis tool it seems like it's more likely to harm users (api is reporting incorrectly, sensor is faulty etc) than slow down reverse engineering much.
This is probably either a ‘grab whatever you can’ or a panopticlick-like strategy though.
These kinds of VPN services have always seemed shady to me.