In a new academic paper, researchers from the Belgian university KU Leuven detailed their findings when they analyzed 15 popular dating apps. Of those, Badoo, Bumble, Grindr, happn, Hinge and Hily all had the same vulnerability that could have helped a malicious user to identify the near-exact location of another user, according to the researchers.
While neither of those apps share exact locations when displaying the distance between users on their profiles, they did use exact locations for the “filters” feature of the apps. Generally speaking, by using filters, users can tailor their search for a partner based on criteria like age, height, what type of relationship they are looking for and, crucially, distance.
To pinpoint the exact location of a target user, the researchers used a novel technique they call “oracle trilateration.”
The good news is that all the apps that had these issues, and that the researchers reached out to, have now changed how distance filters work and are not vulnerable to the oracle trilateration technique.
Neither Badoo, which is owned by Bumble, nor Hinge responded to a request for comment.
I understand trilateration, but what’s “oracle trilateration”? How did these dating apps share the proximity distance of a user and to what precision? Like if it said the user is 5km away, that is still going to give a pretty big area if someone were to trilateral it because the line of the circle would have to include 4.5-5.5km away. Do that three times, and we’d get an area of about a square km. To get it down to 2m, the app would have to be precise to the meter, such as “user is 5,000m away”.
Oracle trilateration refers to an attack on apps that have filters like “only show users closer than 5 km”. In case of the vulnerable apps, this was very accurate, so the attacker could change their position from the victim (which does not require physical movement, the application has to trust your device on this, so the position can be spoofed) until the victim disappeared from the list, and end up a point that is almost exactly 5 km from the victim.
This does not help, since the attacker can find a point where it switches between 4 km and 5 km, and then this point (in the simplest case) is exactly 4.5 km from the victim. The paper refers to this as rounded distance trilateration.
I see so so many timers that round down, so 1.4 seconds = 1 second, 0.4 = 0… so after reaching 0 you have to wait some more. Crazy how people get stuff like that wrong.