Live data from Hacker News

Thieves boosting signal from key fobs inside homes to steal vehicles

cbc.ca

171–180 of 449 posts

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#171
post #162
post #105

I imagine improvements to the key fob could be made that would require a mechanical coupling with the car in order to start it. That would circumvent this attack.

My Tesla requires a pin to drive like a phone

That was rolled out in a recent update, right?

I think the over-the-air updates is one of the big advantages that Tesla has right now. They can respond quickly to critical vulnerabilities like that.

I wonder how fast other car manufacturers are going to catch up? Volvo recently announced that they are working on an Android based system, but it's not going to be rolled out before 2020.

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#172

Another commentor describes the key handshake. The car emits a high frequency wake up signal, the key receives the signal and emits a low frequency unlock code. It is hard to restrict the time of the unlock code because it's low frequency limits the accuracy of your clock. Could you Honeypot the cars wake up signal? If the car detects a delayed broadcast of it's wake up signal it could trigger an alarm or at disable…

> Could you Honeypot the cars wake up signal? If the car detects a delayed broadcast of it's wake up signal it could trigger an alarm or at disable keyless entry. The high frequency signal will have lower tolerances for a timing check.

If the repeater is directional / shielded on the side toward the car, I'd think it would be impossible to distinguish echoes of a repeated signal from normal echoes.

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#173

Nothing new, has been going on for a while now. Market is already providing your own "cage of Faraday[0]" for your fob. [0] https://www.amazon.com/faraday-cage-key-fob/s?page=1&rh=i%3A...

I use these Faraday cage pouches for my new car keys (I got the two-pack listed "Amazon choice" in the above link) and they are excellent. As far as I can tell anyhow - my car hasn't been stolen (yet!) and if I keep the key in it's pouch I can neither open the doors or start the engine even if I'm right next to the vehicle.

An added bonus, it also makes the keys much more comfortable to have in a pocket, holds them in a fairly flat orientation - and stops them from scratching a phone!

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#175
post #81

Earlier quoted context omitted.

It's not a show-stopper. It's not even close to being a show-stopper any more than having keys is also a vulnerability to having a car stolen. All you have to do is keep the fob inside a shielded case at home and you're fine.

> All you have to do is keep the fob inside a shielded case at home and you're fine. Because we all have Faraday cages in our homes, and I'm sure the salesman who sold the car also made the customer aware of this vulnerability. /sarcasm.

>Because we all have Faraday cages in our homes

Yes, most people who own cars new enough to have this vulnerability own microwave ovens.

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#176
post #108
post #74

Earlier quoted context omitted.

The vulnerability is pretty much inherent to the idea. No amount of encryption can protect you from a relay attack. The only foolproof mitigation is to enforce a short round trip time to ensure the fob is actually close to the car, but with the short distances involved that means the fob has to generate and transmit a response within a few nanoseconds.

Embedded devices can be laggy at times. More efficient for the car to estimate the distance and power of the transmitter.

You’ll just estimate the distance and power of the relay. Roundtrip delay is the only thing you can’t fake.

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#178
> Key fobs are constantly broadcasting a signal that communicates with a specific vehicle, he said, and when it comes into a close enough range, the vehicle will open and start.

It's a poor design for the system to take any access-escalating action without an explicit command from the user that initiates a secured transaction that is resistant to MITM.

It's poor design to assume that the range is based on raw signal strength; it should use round-trip-time measurements (for packets exchanged with MITM resistance).

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#179
post #147

Earlier quoted context omitted.

What vehicle do you have?

A 9 year old BMW without the comfort access package.

My BMW did not come with such a fob slot but still required you to dig the key out to press the (un)lock buttons. Weird transition.

Re: Thieves boosting signal from key fobs inside homes to steal vehicles

#180
post #158
post #105

I imagine improvements to the key fob could be made that would require a mechanical coupling with the car in order to start it. That would circumvent this attack.

A simple on/off button on the fob would work, and probably extend the battery life by a few years.

Ah, yes, let's put the burden back on the user after we promised them something easier.

We should just go back to traditional keys if this is the case.

Post reply on HN