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Bluetooth signals can be used to identify and track smartphones

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Re: Bluetooth signals can be used to identify and track smartphones

#71

Post by froh »

eternityforest wrote: post #66
blkhawk wrote: post #54

Earlier quoted context omitted.

yes, a private company that has bought the information can just chose to share it for a fee with anybody it likes. Why would a judge be involved in that?

The GDPR type laws seem to imply that information can't ever really be sold, since consent is always revokable, and can't be required as a condition of using the service. I have a bit of an issue with that, since one generally expects that they can license any data they own, and it makes things like model releases confusing. And the laws seem to define new private spaces that formerly didn't have expectation of priva…

Well that's the idea that data that pertains to you, personally as individual human being, is and remind yours, to protect you from any intrusion.

Cambridge Analytica Style desinformation targeting is just one option. Personal location and contact info can easily be used for criminal or political abuse.

Re: Bluetooth signals can be used to identify and track smartphones

#72

Post by quitit »

kube-system wrote: post #14

> It’s the first time researchers have demonstrated it’s feasible to track individuals using Bluetooth wat.jpg Google scholar has papers going back at least 18 years on this.

Oh god, I'm not insane. This is definitely not a new surveillance vector and there are clear techniques to overcome it without meaningfully interfering with signal or performance. It also reminds me of some of the older copy-protection technologies which relied on a comparable idea of checking for expected variation at a level above the actual data stream.

Re: Bluetooth signals can be used to identify and track smartphones

#74

Post by dontbenebby »

First time?

This has been known for years, check out https://wigle.net/

Here's a Defcon talk on it as well: https://www.youtube.com/watch?v=fSsTgazmHCw

(You can go opt out, but if you didn't know it existed, you've been in there a while. It's why I like to turn off my radios when not using them.)

Re: Bluetooth signals can be used to identify and track smartphones

#75

Post by midislack »

azinman2 wrote: post #57
kube-system wrote: post #14

> It’s the first time researchers have demonstrated it’s feasible to track individuals using Bluetooth wat.jpg Google scholar has papers going back at least 18 years on this.

Except it’s not based on broadcasted identifiers which is what you’re citing.

That'd be much more sensible and easy and it's already known and practical.

Re: Bluetooth signals can be used to identify and track smartphones

#76

Post by midislack »

kalleboo wrote: post #61
sieabah wrote: post #12

Was this not apparent when every manufacturer was working on Covid tracking in the open? Were people really not aware of the technologies being employed? That technology now exists on every phone that has had any semblance of an update in the past two years. There is no privacy, you have always been and will always be completely trackable. You can even use ultrasonic sound signatures so your phone doesn't even need t…

You're being downvoted because this is a completely different technology from the covid tracking. For one thing, the covid tracking had to be explicitly installed and enabled, whereas this works passively.

Many nations enabled it without the consent of their citizenry.

Re: Bluetooth signals can be used to identify and track smartphones

#77

Post by femto »

mleonhard wrote: post #68
femto wrote: post #32

Earlier quoted context omitted.

Section IV of the paper, "Challenges", is interesting reading. As expected CFO displays a strong temperature dependence, causing wrong identifications. Further, I/Q characteristics tend to be close for a given chipset, so I/Q imperfections are more or less identifying the chipset. It's easy to detect different models of phone, but harder to detect individual phones. It doesn't strike me as a serious threat (yet). A f…

Does this mean that a listener can know whether the phone is indoors, outdoors, in a warm pocket, or held in the hand?

From the CFO the listener could tell what temperature changes the phone is undergoing, but the units would not be calibrated. It you knew the temperature of the phone at a couple of different points then you could derive calibration coefficients to get an absolute temperature. If the CFO temperature dependence turned out to be repeatable between phones then knowing the model of the surveilled phone you might be able to calibrate with only one known temperature, or none if the CFO characteristics are the same for all phones (unlikely).

Re: Bluetooth signals can be used to identify and track smartphones

#78

Post by femto »

froh wrote: post #53
superkuh wrote: post #47

If your phone is transmitting radio signals it is identifiable and trackable. A smart phones' primary feature and defining feature is transmitting radio signals. I don't think anyone is surprised at these "anonymous" bluetooth functions being deanonymized. But at least bluetooth beacons aren't going to go very far. Multi-lateration of cell phone radio transmission via precise shared clocks at the base stations gives…

> In the USA this stored by telcos for 2-5 years and is often sold to both private and government purchasers. To private purchasers? For 2-5 years? No need for a judge issued warrant? Just sold?

Triangulation of mobile phones was developed by Cambridge Positioning Systems, back in 1993. It's been part of mobile networks for a long time so telcos have had a lot of time to figure out ways to extract money from location data.

https://www.mrao.cam.ac.uk/~pjds/temp/index.htm

https://www.theguardian.com/technology/2000/aug/17/efinance....

Re: Bluetooth signals can be used to identify and track smartphones

#79

Post by kube-system »

azinman2 wrote: post #57
kube-system wrote: post #14

> It’s the first time researchers have demonstrated it’s feasible to track individuals using Bluetooth wat.jpg Google scholar has papers going back at least 18 years on this.

Except it’s not based on broadcasted identifiers which is what you’re citing.

I know. I did read further. The press release summary is missing so many details that it’s just wrong, though.

Re: Bluetooth signals can be used to identify and track smartphones

#80

Post by superkuh »

froh wrote: post #53
superkuh wrote: post #47

If your phone is transmitting radio signals it is identifiable and trackable. A smart phones' primary feature and defining feature is transmitting radio signals. I don't think anyone is surprised at these "anonymous" bluetooth functions being deanonymized. But at least bluetooth beacons aren't going to go very far. Multi-lateration of cell phone radio transmission via precise shared clocks at the base stations gives…

> In the USA this stored by telcos for 2-5 years and is often sold to both private and government purchasers. To private purchasers? For 2-5 years? No need for a judge issued warrant? Just sold?

It was true for most of my life in the USA. I looked up the information again, now, and it seems in 2018 there was a supreme court decision that made it illegal for cops (but not the NSA, etc) to acquire individual location data without a warrant, https://www.npr.org/2018/06/22/605007387/supreme-court-rules... .

But this doesn't apply to selling to private companies who then sell their services to the government. And it also doesn't apply to the "anonymized" aggregate data of all locations of all cell users. This is still available and sold to both private and direct government purchasers. And with 2-5 years of high cadence 100m data it's very easy to see where someone lives, works, etc and de-anonymize their paths. The commercial sale of this is big business and has been covered innumberable times on HN over the years.

https://news.ycombinator.com/item?id=17094213 , https://news.ycombinator.com/item?id=17081684 , https://news.ycombinator.com/item?id=17069459

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