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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

#21

Post by smithza »

mmastrac wrote: post #16

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.

Apple will probably say something to the effect of, "we didn't have to put anti-stalking technology in, and it works well for the 99% of use cases." The common stalker will not have the technical skills to build their own custom-firmware version of a BLE-enabled system. I don't think this revelation will kill the product line.

Re: Find You: Building a stealth AirTag clone

#22

Post by mmastrac »

smithza wrote: post #21
mmastrac wrote: post #16

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.

Apple will probably say something to the effect of, "we didn't have to put anti-stalking technology in, and it works well for the 99% of use cases." The common stalker will not have the technical skills to build their own custom-firmware version of a BLE-enabled system. I don't think this revelation will kill the product line.

After reading more about this on the attached repo, I think we're going to see some AliExpress clones popping up pretty quick. AirTags appear to be pretty minimal tech - much less complex than I had thought if you exclude the high-precision location finder.

Re: Find You: Building a stealth AirTag clone

#23

Post by eyeeyesawayyy »

noja wrote: post #3

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

Airtags are unique in that they use every iphone in the world as part of the network which tracks them and reports their locations.

So, unlike GPS trackers or competing Bluetooth trackers, AirTags can do two things:

* Last for a very long time on a small battery, no recharging required.

* Reliably report location anywhere in the world that an ordinary person is likely to be.

Re: Find You: Building a stealth AirTag clone

#24

Post by smithza »

mmastrac wrote: post #22
smithza wrote: post #21

Earlier quoted context omitted.

Apple will probably say something to the effect of, "we didn't have to put anti-stalking technology in, and it works well for the 99% of use cases." The common stalker will not have the technical skills to build their own custom-firmware version of a BLE-enabled system. I don't think this revelation will kill the product line.

After reading more about this on the attached repo, I think we're going to see some AliExpress clones popping up pretty quick. AirTags appear to be pretty minimal tech - much less complex than I had thought if you exclude the high-precision location finder.

It is a difficult technical problem for Apple to solve all of the corner-cases. The article shows the screenshot of seemingly 100 unique FindMy devices around this guy's personal residence... there may be some characterization work that can help solve that so an iPhone user would get the alert message. But Apple will continue to promote it and dismiss or downplay these security concerns.

Re: Find You: Building a stealth AirTag clone

#25

Post by LeoPanthera »

rahimnathwani wrote: post #20
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.

> using a cellular modem requires a high capacity battery

The example third party AirTag clone described on the linked page is powered by a full size USB power bank.

Re: Find You: Building a stealth AirTag clone

#26

Post by mox1 »

smithza wrote: post #24
mmastrac wrote: post #22

Earlier quoted context omitted.

After reading more about this on the attached repo, I think we're going to see some AliExpress clones popping up pretty quick. AirTags appear to be pretty minimal tech - much less complex than I had thought if you exclude the high-precision location finder.

It is a difficult technical problem for Apple to solve all of the corner-cases. The article shows the screenshot of seemingly 100 unique FindMy devices around this guy's personal residence... there may be some characterization work that can help solve that so an iPhone user would get the alert message. But Apple will continue to promote it and dismiss or downplay these security concerns.

The problem is easy to solve, just store copies of all public keys of each air tag you send out.

Air Tag messages with unknown public keys just get dropped on their server side checks.

Re: Find You: Building a stealth AirTag clone

#27

Post by cure »

Scoundreller wrote: post #18
scoopertrooper wrote: post #11

Earlier quoted context omitted.

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

There's also the helium network (https://explorer.helium.com/) which has a surprising amount of coverage, especially in urban areas.

Re: Find You: Building a stealth AirTag clone

#28

Post by Shank »

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…

> 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.

They're on Amazon, for $50-150 [0]. The first result for "GPS tracker" I found has 10 days of battery life, which is a fair negative, but you can do a lot to someone if you follow them for 10 days.

[0]: https://smile.amazon.com/LandAirSea-Waterproof-Magnetic-Pers...

Re: Find You: Building a stealth AirTag clone

#29

Post by Friday_ »

Scoundreller wrote: post #18
scoopertrooper wrote: post #11

Earlier quoted context omitted.

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

This looks interesting, but device itself looks like it wouldn't survive fall on the floor, let alone armageddon. Just joking.

Re: Find You: Building a stealth AirTag clone

#30

Post by IshKebab »

mmastrac wrote: post #16

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.

Yeah I don't understand this. Surely airtags have to be registered, and when an iPhone sees tag 3957375967 Apple's servers look that up and say "oh it's registered to Billy Bob; I'll tell them".

But if your fake airtag rotates through 2000 IDs how do you register them all?

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