Abusing WebRTC to reveal coarse location data in Signal
The only universal fix I can think of for this class of attacks is to have routers bound latency to a lower limit (eg. 200ms), with fixed latency buckets (eg. 500ms granularity) when it goes beyond that.That is, no traffic would traverse the router in less than 200ms, and every other flow would be fixed at 700ms, 1200ms, 1700ms, etc amounts of latency. Tweaked correctly that would limit location to continent, unless I'm missing something.It would effectively trade quick responses to/from close networks for some extra amount of privacy (in the case that GeoIP has already been taken care of)The latency would have to be controlled on both ingress and egress to account for internal and external threats. I've got a niggling feeling that an attacker that could control latency of enough geographically diverse networks could find the boundary by manipulating responses to get finer detail, but can't quite work the problem into a solution...Is there a less horrible or more reliable universal mitigation that I'm not thinking of?