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Find You: Building a stealth AirTag clone

positive.security

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Re: Find You: Building a stealth AirTag clone

#11

Post by scoopertrooper »

cure wrote: post #9
mckirk wrote: post #8

Earlier quoted context omitted.

You also need a way to communicate back the tracking results, which presumably implies a SIM card and thus more opportunity to get detected (and linked back to you). But yes, in theory you can (and always could) do that. The barrier to entry would be a lot higher though, as all that's needed here is 'microcontroller with Bluetooth'. And that really makes it dangerously easy.

> You also need a way to communicate back the tracking results, which presumably implies a SIM card and thus more opportunity to get detected (and linked back to you). But yes, in theory you can (and always could) do that. I think gp included the lorawan for that purpose. No SIM required.

You'd also need a LoRaWAN network to hook into.

But most importantly, I doubt you could build a LoRaWAN tracker as compactly as an AirTag. A beacon would use significantly less electricity and therefore require a smaller battery.

Below is one of the smallest LoRaWAN modems on the market, which by itself is marginally bigger than an AirTag. Now add batteries, GPS, antennas, and an SoC to drive the whole thing.

https://www.murata.com/en-eu/news/connectivitymodule/lpwa/20...

Re: Find You: Building a stealth AirTag clone

#12

Post by kelnos »

Crosseye_Jack wrote: post #7
tiarafawn wrote: post #5

Earlier quoted context omitted.

If they need to rely on their own GPS and internet uplink rather than just bluetooth, they would be much more expensive

But not that much more even in small quantities. If you exclude the time to dev the software, design the PCB, and assemble the tracker then you can knock up a NB-IOT module + GPS module + Microcontroller & supporting parts (to tie the two modules together) for about $30-$35 in small quantities, keep your data usage low and you can throw in a pre-paid IOT-NB sim for about $15. EDIT: Its not gonna be as small as a AirT…

Sure, but I hope it's easy to understand that it's orders of magnitude easier to just buy an AirTag (including "silenced" ones from eBay or wherever) and drop it in someones purse or coat pocket, or attach it to their car.

Pretty much no regular stalker is going to design and build their own GPS+cellular tracker. Even if someone were to do that and then sell them online, the barrier to finding and buying those are still probably going to be higher than getting an AirTag. And the battery won't last anywhere near as long as well. And also consider that the software running on it, as well as the cloud service that lets you check the location, doesn't just magically appear either. Someone has to build and host that as well. Even a lower-tech solution that just emails a location report every few minutes still requires work to build.

Yes, it's absolutely possible, and not super difficult, to track someone using a GPS+cellular device. But it feels really disingenuous to claim that tracking people was just as easy to do for your average stalker pre-AirTags.

Re: Find You: Building a stealth AirTag clone

#13

Post by kelnos »

Friday_ wrote: post #6

Why not build your own tracker that doesn't rely on Apple. You only have to have GPS, LoRaWAN, MCU, battery, and antenna, That's about it.

You or I could probably do that, but that's well beyond the technical capabilities of your average would-be stalker.

Re: Find You: Building a stealth AirTag clone

#14

Post by Scoundreller »

CharlesW wrote: post #4
noja wrote: post #3

Other trackers don't tell you they are tracking you though, what about those.

I understand your point and it's completely valid, but I think the difference is that Apple is mainstreaming personal tracking in a way that other companies could only dream of, and in doing so is also mainstreaming awareness of how technologies like this might be abused. Because of this, Apple has painted a giant target on their back even though they're arguably handling privacy issues better than anyone else in thi…

I think what Apple is really mainstreaming is the mass-use of their devices as a low-bitrate, irregular sneakernet. This should replace lots of IoT stuff.

It's kinda dumb that our cabin has a 'smart' meter on a meshnetwork, but there's no way for me to remotely turn-on a heater 4h before I arrive without a $10+/month subscription.

Maybe one day I can offline order a book and it just shows up because the on-line devices nearby (or are likely to show up nearby) can drop it off wirelessly.

A traffic light won't be needing its own internet subscription or private physical network to beam up a picture of the intersection or status.

Re: Find You: Building a stealth AirTag clone

#15

Post by Crosseye_Jack »

kelnos wrote: post #12
Crosseye_Jack wrote: post #7

Earlier quoted context omitted.

But not that much more even in small quantities. If you exclude the time to dev the software, design the PCB, and assemble the tracker then you can knock up a NB-IOT module + GPS module + Microcontroller & supporting parts (to tie the two modules together) for about $30-$35 in small quantities, keep your data usage low and you can throw in a pre-paid IOT-NB sim for about $15. EDIT: Its not gonna be as small as a AirT…

Sure, but I hope it's easy to understand that it's orders of magnitude easier to just buy an AirTag (including "silenced" ones from eBay or wherever) and drop it in someones purse or coat pocket, or attach it to their car. Pretty much no regular stalker is going to design and build their own GPS+cellular tracker. Even if someone were to do that and then sell them online, the barrier to finding and buying those are st…

> Sure, but I hope it's easy to understand that it's orders of magnitude easier to just buy an AirTag

Oh yeah, Was just pointing out that the pricing of such things is dropping like flies.

> Pretty much no regular stalker is going to design and build their own GPS+cellular tracker.

Agreed, again was just pointing out the pricing of parts.

> Yes, it's absolutely possible, and not super difficult, to track someone using a GPS+cellular device. But it feels really disingenuous to claim that tracking people was just as easy to do for your average stalker pre-AirTags.

I don't think I did claim that. I wasn't trying to claim that. Maybe thats just the limitation of using text.

Re: Find You: Building a stealth AirTag clone

#16

Post by mmastrac »

Does this mean that Apple is failing to validate the capability of things that purport to be AirTags? Or that the BLE protocol is just not powerful enough to have Apple signatures on each broadcast public key?

If it's the latter, it might mean that the entire AirTag product line is dead in the water.

Re: Find You: Building a stealth AirTag clone

#17

Post by giaour »

noja wrote: post #3

Other trackers don't tell you they are tracking you though, what about those.

You can purchase pre-made GPS+cellular trackers, but it seems like it would be much easier to tie a detected tracker of this type back to a specific person. A tracker with cellular capability will have a SIM and some kind of subpoena-able service record, while one of the pirate AirTags described in the post is basically just an antenna and a battery.

Re: Find You: Building a stealth AirTag clone

#18

Post by Scoundreller »

scoopertrooper wrote: post #11
cure wrote: post #9

Earlier quoted context omitted.

> You also need a way to communicate back the tracking results, which presumably implies a SIM card and thus more opportunity to get detected (and linked back to you). But yes, in theory you can (and always could) do that. I think gp included the lorawan for that purpose. No SIM required.

You'd also need a LoRaWAN network to hook into. But most importantly, I doubt you could build a LoRaWAN tracker as compactly as an AirTag. A beacon would use significantly less electricity and therefore require a smaller battery. Below is one of the smallest LoRaWAN modems on the market, which by itself is marginally bigger than an AirTag. Now add batteries, GPS, antennas, and an SoC to drive the whole thing. https:/…

There are some groups building 'armageddon' mesh-based hand-held communicators like Meshtastic. Converged hardware is already there. The network probably is too in more and more metros if you're not within a few km of what you're trying to communicate with/track.

https://meshtastic.org

Map: https://canvis.app/meshtastic-map

Re: Find You: Building a stealth AirTag clone

#19

Post by giaour »

Friday_ wrote: post #6

Why not build your own tracker that doesn't rely on Apple. You only have to have GPS, LoRaWAN, MCU, battery, and antenna, That's about it.

Can you get onto a lorawan network without some kind of service contract? Seems like it would leave a paper trail for investigators to follow, whereas the pirate AirTags described in the article are anonymous commodity hardware using the victim's Apple devices for connectivity.

Re: Find You: Building a stealth AirTag clone

#20

Post by rahimnathwani »

Friday_ wrote: post #6

Why not build your own tracker that doesn't rely on Apple. You only have to have GPS, LoRaWAN, MCU, battery, and antenna, That's about it.

Because:

- using a cellular modem requires a high capacity battery

- if you hide a tracker well, it probably won't have a good GPS reception

Apple's BLE-based network solves both of these problems.

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