Telegram publishes users' locations online

Post by meowface » Tue, Jan 05, 2021, 5:04 AM UTC

dawnerd wrote: post #25

mercora wrote: post #18

so i know some people around me who are using telegram and very likely most of them did not change anything about their privacy settings as usual. However, i do not see any of them in the list and it even shows me users some 10km away. When viewing this list on the top it has a button to make yourself visible so i assume if you don't do it voluntarily its not broadcasted at all which appears to be a non issue then, l…

Yeah its very much opt in so Im not sure what the real issue is apart from being somewhat granular. How granular telegram makes it is the question. From the article the way they asked didn't sound like it was "do you live at 123 something st" but instead are you by, which even if you were a few blocks off someone might say yes. For all we know Telegram is doing some rounding. Gonna need to test some more to see I gue…

Post by godelski » Tue, Jan 05, 2021, 5:08 AM UTC

plumeria wrote: post #42

gruez wrote: post #6

>[Line] fixed it by adding a random number to the user's destination This is a imperfect solution. There's two possibilities: the offset (aka "random number") is dynamic, or it's fixed. If it's the former all you have to do is sample enough times to get through the noise. If it's the latter, it's not vulnerable to the previous attack, but if you have a known point of reference (so you can deduce what the offset is),…

Would showing something like “5 mins away“ instead of “800 m” be a simple solution?

Post by bigiain » Tue, Jan 05, 2021, 5:09 AM UTC

cwhiz wrote: post #41

arthurcolle wrote: post #7

It's a shame that people still use Telegram when Signal is so much better, and has better credentials all around.

Signal is terrible. I use the app still, but it’s horribly buggy. The disappearing messages, a hallmark feature, is fundamentally broken in some way that I can’t fully comprehend. Totally unreliable. Telegram is better in every way... except security.

Post by dheera » Tue, Jan 05, 2021, 5:13 AM UTC

rlpb wrote: post #23

gruez wrote: post #6

>[Line] fixed it by adding a random number to the user's destination This is a imperfect solution. There's two possibilities: the offset (aka "random number") is dynamic, or it's fixed. If it's the former all you have to do is sample enough times to get through the noise. If it's the latter, it's not vulnerable to the previous attack, but if you have a known point of reference (so you can deduce what the offset is),…

If it's a fixed offset for a particular person, then isn't that just another variable in a simultaneous equation? You'd just need one more sample to solve for it.

Post by sudosysgen » Tue, Jan 05, 2021, 5:18 AM UTC

est31 wrote: post #55

gruez wrote: post #6

>[Line] fixed it by adding a random number to the user's destination This is a imperfect solution. There's two possibilities: the offset (aka "random number") is dynamic, or it's fixed. If it's the former all you have to do is sample enough times to get through the noise. If it's the latter, it's not vulnerable to the previous attack, but if you have a known point of reference (so you can deduce what the offset is),…

Map cells are the best solution available for 90% of locations, but they don't help with the 10% that's close to map borders. If an user randomly jumps between two map cells you know they live at the boundary. Generally there is often noise in GPS signals so it's likely that person will jump around. Furthermore, if a person uses multiple services, and each service has its own cell layout, you can check all services a…