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What your Bluetooth devices reveal

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Re: What your Bluetooth devices reveal

#101

Post by wolvoleo »

trashb wrote: post #9

> We’ve normalised the idea that Bluetooth is always on. Phones, laptops, smartwatches, headphones, cars, and even medical devices constantly broadcast their presence. The standard response to privacy concerns is usually “nothing to hide, nothing to fear.” I guess anything you send out can be used to profile you. Some of my friends live on a farm near a semi busy road, however far enough from other farms to not be ab…

> 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

They do but most phones rotate the mac adress these days. So while they can still track you through the store (sadly) they don't have the ability to track your recurring visits.

I wish phones had the option to constantly spam broadcasts with random MAC ids. That would make the practice useless.

Re: What your Bluetooth devices reveal

#102

Post by joemi »

SoftTalker wrote: post #20
trashb wrote: post #9

> We’ve normalised the idea that Bluetooth is always on. Phones, laptops, smartwatches, headphones, cars, and even medical devices constantly broadcast their presence. The standard response to privacy concerns is usually “nothing to hide, nothing to fear.” I guess anything you send out can be used to profile you. Some of my friends live on a farm near a semi busy road, however far enough from other farms to not be ab…

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

I used to fervently keep my bluetooth off on iOS, and I learned that if you turn it off via the Control Center, then it automatically gets turned back on the next day. But if you turn it off via Settings, then it only gets turned back on when the system software updates. (I stopped doing this a couple iOS versions ago, though, so it may have changed since then.)

Re: What your Bluetooth devices reveal

#103

Post by voidmain0001 »

trashb wrote: post #9

> We’ve normalised the idea that Bluetooth is always on. Phones, laptops, smartwatches, headphones, cars, and even medical devices constantly broadcast their presence. The standard response to privacy concerns is usually “nothing to hide, nothing to fear.” I guess anything you send out can be used to profile you. Some of my friends live on a farm near a semi busy road, however far enough from other farms to not be ab…

Sure, stores use WiFi access points and BT to track MAC addresses and BT device IDs. Google does something similar with location and it provides in real time how busy a location is which I find super convenient. It’s a shame that shaping data into useful information also means it can weaponized.

Re: What your Bluetooth devices reveal

#105

Post by gruez »

bigiain wrote: post #98
gruez wrote: post #94

Earlier quoted context omitted.

>That's a problam (one of many problems) with WiFi MAC address randomisation - you can sniff the network names a phone is trying to connect to, then stand up a wifi access point with one of those names and the phone will reveal its real MAC address when it connects. That's not how mac address randomization works now for both android and ios. Both connects with a randomized mac as well, which might be persistent per-n…

Oh cool, thanks. My last time playing with this was pre covid, possibly 5 or more years pre covid. I do know for sure that my iOS devices connect with persistent MAC addresses on both my home and work wifi networks - I'd _assumed_ it was the same MAC address on both networks, but I'll be curious to see if that's correct next time I'm in the office.

You don't even need to be in the office to see it. Just go to wifi -> edit, and it'll bring up a list of saved networks. Tap on one of them and it'll show the mac address used.

Re: What your Bluetooth devices reveal

#106

Post by wolvoleo »

jorvi wrote: post #72
trashb wrote: post #9

> We’ve normalised the idea that Bluetooth is always on. Phones, laptops, smartwatches, headphones, cars, and even medical devices constantly broadcast their presence. The standard response to privacy concerns is usually “nothing to hide, nothing to fear.” I guess anything you send out can be used to profile you. Some of my friends live on a farm near a semi busy road, however far enough from other farms to not be ab…

> 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 .

True but I wouldn't put it past them tbh. It's very easy to hide or claim a 'misconfiguration'.

Even the airports here track everyone. They say it's for public safety but I'm sure they use it for market analysis for their expensive sandwich shops too.

Re: What your Bluetooth devices reveal

#107

Post by wolvoleo »

0x1ch wrote: post #19
pixl97 wrote: post #12

Earlier quoted context omitted.

> 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.

I was wardriving my neighborhood and realized my elderly neighbor's CPAP machine is broadcasting some type of BT signal 24/7. I imagine it's transmitting some important stats, but it did make me have a 2nd thought about medical devices being IoT or BT enabled.

Yeah I always keep my cpap on airplane mode. It even had 5G. The therapist complains they can't monitor it but I have to come in with the machine and SD card every few months so they can check it then. They don't need 24/7 access.

What bothers me more is that my sex toys broadcast on Bluetooth even when I'm using them through WiFi. It even says the brand in the device name.

Not that I give a fuck what the neighbours think but it's just none of their business. And some toys are for discreet outdoor use too. Though that's not my thing.

In the past I renamed one of my phones to "Lovense Hush" to troll, though I've never seen anyone looking suspiciously. I guess most people aren't creeps like me who check stuff like that :)

Re: What your Bluetooth devices reveal

#108

Post by wolvoleo »

_slih wrote: post #31

ran something similar on a home network once and was surprised how many of my neighbors' devices showed up with full manufacturer names and model numbers. you don't even need to try hard.

Yeah here in the city I scan for 2 minutes and I know half the neighbours names and what phones, computers and TVs they use.

Re: What your Bluetooth devices reveal

#109

Post by fer »

TheSilva wrote: post #2

Tangential, sort of: in the early days of mobile phones for the masses, when there was no WiFi/3G in the underground, I will often enable Bluetooth in my phone, look for nearby devices and try to match names and looks. That was before everyone had their "John's IPhone" or "Samsung A55" boring names everywhere and some of us cared to personalise our device's name. Anyone else played this game?

What I remember is that you could push OBEX calendar objects without much refusal from the phones and make people have alarms ringing at 3am, fun times!

Re: What your Bluetooth devices reveal

#110

Post by jerlam »

joemi wrote: post #102
SoftTalker wrote: post #20

Earlier quoted context omitted.

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

I used to fervently keep my bluetooth off on iOS, and I learned that if you turn it off via the Control Center, then it automatically gets turned back on the next day. But if you turn it off via Settings, then it only gets turned back on when the system software updates. (I stopped doing this a couple iOS versions ago, though, so it may have changed since then.)

Bluetooth (and wifi) aren't turned off at all through the Control Center - they changed the wording to say "disconnected", meaning that your phone only disconnects from known devices. But both are still turned on for other purposes such as CarPlay, Handoff, and Location Services (via wifi). For the purposes of this discussion, they are potentially still transmitting a known identifier.

Apple reconnects to known devices and networks at 5am:

https://support.apple.com/en-us/102412

Bluetooth and Wi-Fi Aren't Fully Disabled When Off in iOS 11 Control Center

https://news.ycombinator.com/item?id=15297387 (2017, 143 comments)

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