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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

#11
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 feature is when you walk away (a few seconds after you're out of range), the doors automatically lock. However, the downside of this feature is my wife's car does not have it -- and so at least half of the time when I am driving it I forget and leave it unlocked in parking lots.

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

#13
post #2

But people still blindly trust carmakers to make reliable and difficult to hack fully software-based and with always-on internet access self-driving vehicles. They can't even secure the thing that directly unlocks your car and enables thieves to steal it.

It is a legitimate point to a degree, vehicle makers have a long track record of terrible software, and now they want to go headlong into one of the most complicated software projects ever attempted by man.

It will be interesting to see how legal liability shapes up with self-driving.

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

#14
post #11
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…

Oldest car I've seen it in is a 2006 Infiniti.

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

#16
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.

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

#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 exact opposite approach with their expensive vehicles - they leave the key in plain sight near the front door, so if someone wants to steal the car using this method they can do so without entering the house or if they do break in they will(hopefully) take the key and leave, without threatening and possibly harming their family. I'm not sure which way is better - preventing the thief from stealing your vehicle and risk that they will then decide to break in and get the key from you, or let them steal it and just deal with insurance later.

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

#18
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.

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

#19
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.

>>Why is it transmitting without the user pressing a button? Is that a feature?

It's not transmitting anything, it works pretty much the same way NFC works. Both the key and the car have their own public/private key pairs(which were obviously set by the manufacturer) and when you touch the handle the car transmits an unlock request to the key, encrypted with the car key's public key(this is going to get confusing lol) - when the key receives the message, it decrypts it using its own private key, if it's correct then it replies with an "ok" message encrypted with the car's public key. When the car receives that it decrypts it using its own private encryption key and opens the doors. Simple, and in theory unbreakable. The issue is that the car doesn't measure how far away from vehicle the key is - it only relies on the fact that the transmitters used by the car and the key are super-low range(like, within 50cm). Which is obviously defeated by using signal boosters.

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

#20

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.

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