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Thieves boosting signal from key fobs inside homes to steal vehicles

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

#21

Post by nickspacek »

josefresco wrote: post #16
z2 wrote: post #5

Two factor authentication for cars, here we come! Though, searching for this phenomenon shows articles at least 3 years old warning to get Faraday cages or otherwise wrap fobs in aluminum foil. But do they really transmit all the time, or do they contain accelerometers or something to prevent battery from being wasted?

2FA seems to make sense. Maybe a 4-6 digit pin that would be optional for those in high risk areas/situations. > But do they really transmit all the time, or do they contain accelerators or something to prevent battery from being wasted? I'm curious about this as well. A family member has an older Nissan with a keyless fob and I don't recall them ever having to replace batteries/keyfobs.

The fob for my 2007 Altima with keyless start (not entry) has required at least one battery change since I inherited it and is now complaining that the battery is getting low.

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

#22

Post by eyeinthepyramid »

z2 wrote: post #5

Two factor authentication for cars, here we come! Though, searching for this phenomenon shows articles at least 3 years old warning to get Faraday cages or otherwise wrap fobs in aluminum foil. But do they really transmit all the time, or do they contain accelerometers or something to prevent battery from being wasted?

For the 2nd factor, they should have some kind of non-electronic device which when inserted and turned, would allow the activation of the door and ignition of the car.

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

#23

Post by retSava »

gambiting wrote: post #17

I already put mine in a metalic bag for the night, or just press the "lock" button twice which disables the keyless entry system entirely. Manufacturers really need to hurry up and implement more accurate timing detection in the keys - it should be absolutely trivial to detect how far away the key is based on the response time, but for some reason manufacturers don't do this yet. Edit: I also know people who take the…

I don't think it's the distance really, it's the relaying and the additional steps that adds latency. If the data rate is low, and the data is not trivially small (ie over some 10s or 100s of bytes), you are in the milliseconds area, which should be very easily tracked.

Perhaps if the keyfob needs to do some additional conditioning on the data (eg some decryption+encryption), or is very slow, the extra overhead of the relay is small in comparison.

I don't know how the keyfob conserves power, but I guess some kind of duty cycling the radio, in which the first wake-up latency of the keyfob is not necessarily know beforehand. But, just send a few packets back and forth and get the overall latency and it should be able to determine if a relay is used.

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

#25

Post by ghaff »

gregmac wrote: post #11
snarfy wrote: post #6

> 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. Why is it transmitting without the user pressing a button? Is that a feature? As you walk up to the car it automatically starts like magic? I'm not familiar with these newer cars.

With my car, as soon as you touch the door handle (with the keyfob in your pocket, or within a couple feet of the door) it unlocks, and to start the car you push a button. It doesn't work from even 4' away (eg, someone else touches the door handle while you're close) and it doesn't work from the other side (eg, when the keyfob close enough to driver's side door, the passenger side won't unlock). The really nice featu…

>so at least half of the time when I am driving it I forget and leave it unlocked in parking lots

This is the problem with a lot of the newer tech in cars like backup alarms. You become used to various features in your own car and when you rent a car you need to consciously remember that the vehicle doesn't have $FEATURE. Effectively, cars are becoming a lot less standardized. A car I rented a few weeks ago beeped at me a couple times and it took a while before I realized it was the lane departure warning triggering on a couple turns.

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

#26

Post by ams6110 »

eyeinthepyramid wrote: post #22
z2 wrote: post #5

Two factor authentication for cars, here we come! Though, searching for this phenomenon shows articles at least 3 years old warning to get Faraday cages or otherwise wrap fobs in aluminum foil. But do they really transmit all the time, or do they contain accelerometers or something to prevent battery from being wasted?

For the 2nd factor, they should have some kind of non-electronic device which when inserted and turned, would allow the activation of the door and ignition of the car.

Yeah so funny how all this modern tech can be compromised more easily than an old fashioned mechanical lock and key. And now I need to worry about putting my car key in a Faraday bag when I'm at home? Ridiculous.

And if you lose your key? $$$ to get a new one. Want a copy for safekeeping or because you have additional drivers for the car? More $$$.

If someone wants to get into your car they will. They will just break a window. If they want the whole car they will get it. The only person who is having a more difficult time is the owner.

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

#27

Post by gambiting »

ghaff wrote: post #20
gambiting wrote: post #17

I already put mine in a metalic bag for the night, or just press the "lock" button twice which disables the keyless entry system entirely. Manufacturers really need to hurry up and implement more accurate timing detection in the keys - it should be absolutely trivial to detect how far away the key is based on the response time, but for some reason manufacturers don't do this yet. Edit: I also know people who take the…

> it should be absolutely trivial to detect how far away the key is based on the response time Is that true? Accurate, very low power distance detection has a lot of potential applications (e.g. your phone straying too far away) but BLE (for example) doesn't really work for measuring distance--through signal strength--at all. If it's possible, I'd be very curious how to build such a distance detector.

If you are processing data with nanosecond precision(which is not difficult with modern microchips) then you can tell the distance to the key by just measuring the number of nanoseconds elapsed since the request was sent(accounting for amount of time taken to calculate the response). If you can measure the time in nanoseconds that's good enough to tell the difference between the key being 1m and 10m away.

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

#28

Post by SmellyGeekBoy »

gambiting wrote: post #17

I already put mine in a metalic bag for the night, or just press the "lock" button twice which disables the keyless entry system entirely. Manufacturers really need to hurry up and implement more accurate timing detection in the keys - it should be absolutely trivial to detect how far away the key is based on the response time, but for some reason manufacturers don't do this yet. Edit: I also know people who take the…

> I also know people who take the exact opposite approach with their expensive vehicles - they leave the key in plain sight near the front door

This seems like the best strategy to me. If you have a desirable vehicle and someone decides to break into your house to get hold of the keys they're going to turn the place upside down trying to find them. If you're in at the time you're also putting yourself in a lot of danger.

Just leave the keys by the front door and let the insurance deal with it.

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

#29

Post by hkai »

Tade0 wrote: post #24

It's useful to note that less sophisticated methods still work as well. I used to lease a 2015 Toyota Auris(facelift). One year into the lease someone broke into it smashing the rear-left window and just drove away.

Curious how they started it?

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

#30

Post by logfromblammo »

fabricexpert wrote: post #18
z2 wrote: post #5

Two factor authentication for cars, here we come! Though, searching for this phenomenon shows articles at least 3 years old warning to get Faraday cages or otherwise wrap fobs in aluminum foil. But do they really transmit all the time, or do they contain accelerometers or something to prevent battery from being wasted?

2fa on a car would be a disaster. I can't wait to whip out my phone in the pouring rain, trying to unlock it while my hands are full and I have no signal.

Something you have: keyless fob.

Something you know: numeric unlock code.

Unlocking the doors could be 1FA, but moving the vehicle should require 2FA.

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