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You can do this for much cheaper - all four of your tires are broadcasting a unique ID to report tire pressure, the radio to pick it up is cheap (because cars), and TPMS has no facility to randomize or otherwise secure this.

> I believe shopping malls often use such signals (wifi, bluetooth) to track what your travel pattern through the mall is. They know what section of the store you spend most of your time in and what storefronts you stall at

In the EU this is forbidden unless they explicitly ask your permission. They can still gather aggregate stats but they cannot build a profile on you.

>There where A LOT of access points named "Audi", "BMW", "Tesla" etc.

That's one of the funniest things about wardriving with Wigle on your phone. I can often see the SSID of "Jennifer's Equinox", "Jacks Suburban" right after I get cut off by someone in said vehicle. The vast majority of car bluetooth/wifi I see tends to have varying amounts of identifying information. It's almost as bad as the fact that apple still defaults to Jacks iPhone/iPad etc with no option to rename the device until you've finished setting it up.

Companies are not out to protect us with default settings and the majority of users need to wake up to this fact.

Don't worry about Tesla's being tracked. Via Bluetooth this has existed for at least 7 years [1] (was mentioned on HN as well). Tesla know (also for 7 years), Musk doesn't care 'since license plates can also be tracked'.

I used it in train stations, and get hits when passing highways via train or bus. Esp. fun if you stand still due to traffic lights or traffic jam, since you can try to get a visual.

The only lesson to be learned here is that it allowed one to learn in 2019 Musk is overrated. But you can also learn that lesson from the book The PayPal Wars which predates this by 15 years.

> I believe shopping malls often use such signals (wifi, bluetooth) to track what your travel pattern through the mall is. They know what section of the store you spend most of your time in and what storefronts you stall at.

Not allowed in EU.

[1] https://www.teslaradar.com/

> I believe shopping malls often use such signals (wifi, bluetooth) to track what your travel pattern through the mall is. They know what section of the store you spend most of your time in and what storefronts you stall at.

Yes, I remember Cisco had a product like this all the way back in 2011. They could pinpoint a customer to an exact position inside a store using triangulation, they would know which shelf you spent time in front of etc. In the 15 years since then, I expect the technology is much scarier and intrusive.

There's an Android app that can find devices, make profiles, and you can track location for as long as they're connected. So you can profile passerbys and even get notified when the profile passes through again. I forgot what is was called

> We had a discussion that it would be easy to determine who was passing by at what times due to these especially when you can "de-anonymize" the data for example link it to a numberplate.

You could also read the numberplate directly with OpenALPR. It can be finicky to set up a camera to do this reliably in all conditions (particularly at night and high speed) but once done you could detect any car passing, not just ones with wifi access points.

When the law requires us to have numberplates, I think this just has to be considered public information for anyone who is nearby or can leave a camera nearby. It's not ideal to leak it in additional forms that might be easier for people to grab (say, with an ESP32), but it's a matter of degree rather than of kind.

But yeah, I'm with you on some of these others, particularly the medical devices. That's not great.

The GrapheneOS variant of Android will disable both Bluetooth and WiFi after a set period of inactivity.

There is also a Bluetooth shutoff app on F-Droid.

https://f-droid.org/en/packages/com.mystro256.autooffbluetoo...

I have also put an Airtag clone in my car (Loshall in iOS mode). That is probably leaking my arrival times. My water meter is also now bluetooth.

I disable bluetooth on my phone, though periodically I find that it's back on.

Edit: iOS

> I believe shopping malls often use such signals (wifi, bluetooth) to track what your travel pattern through the mall is.

Many places do this. The department stores in the mall, target, even grocery stores do it.

> even medical devices constantly broadcast their presence

I mean yes, said medical devices are a whole lot less useful to me if they are not transmitting data. For some of this stuff you can't have your cake and eat it too.

hmmmmm...

2006, sat in a job interview. Interviewer says he'll Bluetooth over a file to me - what's by phone's name?

2006, the year that Tool's 10,000 Days had been released, which I was enjoying and, being a bit of an Edge Lord, I'd named my device after a lyric from Vicarious - which, IIRC fit perfectly into the name space and made me very happy:

> ILikeToWatchThingsDie

Excellent. Still got the job though!

Hah, I change my device name and wifi hotspot all the time...

"[Agency-acronym] Surveillance Van #43/44/etc.."

Yeah, but it stopped pretty soon stores figured out that they could flood you with advertisements over Bluetooth. In some places it was bad enough that I had to turn off Bluetooth.

Yep 100% did the same.

It was interesting to see what people named stuff as even back then I figured you could use that metadata for tracking devices...but even more interesting was looking at the Mac address to see the manufacturer and try and find some rare or cool device.

Did you ever try to communicate with them?

https://en.wikipedia.org/wiki/Bluejacking

I do the reverse. I set my wifi hotspot or bluetooth to "MetPoliceUnit355" and I look for people making faces or looking around.

> Bluetooth desperately needs mac randomization.

Bluetooth already has a well developed MAC randomization scheme.

Lookup "resolvable private address". The short of it is, your phone can find your headphones or vice-versa, despite one or both having random addresses. The addresses can be regenerated or rotate at an interval (say 15 minutes). The first part of the address is a nonce (pRand), and the rest of the address is a 24-bit hash of pRand with an identity resolving key (IRK). So the other party just listens passively for addresses, and sees if any of them happen to have the right hash.

I don't think this is as airtight as people think it is. Certainly, if you are following somebody and one address disappears right as another appears (rotation), it's quite easy to infer the new/old addresses belong to one device. I tried briefly to convince the Android developers to synchronize that rotation globally.

You can also probably infer that if you see a pair of random MACs arrive, and they have a certain pattern of timing and payload size, you can say with some certainty that they are particular devices, say an iPhone and an Apple Watch. But that requires sophisticated equipment since most Bluetooth LE communication is over a non-cryptographic frequency hopping arrangement.

Lastly, radio fingerprinting is widely known in academia, but requires special equipment.

Random Bluetooth MACs are already possible. iOS devices have been doing it for years alongside the random Wi-Fi MACs.

Similar story - "Home assistant picked up my neighbours Bluetooth toothbrush and now I can see when they brush their teeth"

https://www.reddit.com/r/homeassistant/comments/1306pcw/home...

That one doesn't seem to do bluetooth at all, I think?

The Hollywood movie Minority Report has a scene where an advertising display personalizes the ad by your name. https://www.youtube.com/watch?v=7bXJ_obaiYQ

The article says the data is in a SQLite database.

Wow e-scooter wardriving is something I hadn’t thought of. Could be happening somewhere

And kismet

In my experience, just fine. I recently ran a large (~30k) marathon and my AirPods and watch never glitched once, streaming the whole time including in the packed start corrals. I had the same thought about RF contention, but Bluetooth didn't seem to care.

Even licensed wireless stops functioning. All circuits are busy.

Possible, but they buy data from the carriers with similar profile possibilities. The DEA operates long standing and pervasive surveillance in “drug corridors” like I-95 from Maine to Miami. They do things like LPR and grabbing passenger pictures.

If Bluetooth is used, it may be a way to get a count of passengers or if the passengers change. I know based on newspaper accounts that they are particularly interested in cars that stop in Philly or Baltimore.

This stuff is frequently used against cops too so they may use the tech in similar ways. If you’re someone worried about getting raided, spotting a large number of new signals at the front door is an early warning potentially.

https://www.kuow.org/stories/privacy-advocates-flag-a-potent...

I remember an art exhibit by an online privacy activist made where it’d ping people’s phones to get a list of “known WiFi networks” and then display them on a screen in a room.

Each person would get a unique fingerprint of named network locations

I believe Houston used bluetooth to measure congestion on 45.