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How some thieves broke into my car and why you're vulnerable too

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Re: How some thieves broke into my car and why you're vulnerable too

#11

Post by emidln »

gnaffle wrote: post #6
gms7777 wrote: post #4

Earlier quoted context omitted.

So I don't know much about either these keyless ignition systems or security and encryption, but is it really that simple? According to my not-super-legitimate internet source ( http://auto.howstuffworks.com/remote-entry2.htm ), typical remote entry keys work with at least 40 bit codes, and different car manufactures use different systems/#s of bits. In additon, since the codes are encrypted with different random #s…

Not sure if it was the case here, but apparently some cars can unlock automatically if the key is nearby. To hack this, you only need a sensitive receiver that can retransmit the signal from the key, and you need two people, on in proximity to the key, and another nearby the car when it unlocks.

That's not really the case. Some of them unlock via low frequency RF, but to my knowledge they still use encryption that uses their button click count as one of the variables plus a shared secret.

Re: How some thieves broke into my car and why you're vulnerable too

#13

Post by Broken_Hippo »

I am very far from alarmed. Though I can think of all of the 'scary' doom scenarios that go along with this, I figured out a long time ago that even my normal barely-running vehicles could be broken into or worse. Any doom beyond that has chances that are more rare than hurting myself while getting into the same car. So I'm not going to worry about it.

I'll continue to take reasonable precautions (don't keep valuables in the vehicle, have insurance, look into the car at night since I rarely lock it, etc). And yes, I rarely lock the car. I figure that a broken window (what I figure is the most common entry) will hurt me more financially and cause more inconvenience than anything in the car.

Technically speaking, if people can get my credit card numbers, it is unsurprising that the door lock technology can be manipulated. Locks never keep the determined out, it merely forces them to work more creatively.

Re: How some thieves broke into my car and why you're vulnerable too

#14

Post by gnaffle »

emidln wrote: post #11
gnaffle wrote: post #6

Earlier quoted context omitted.

Not sure if it was the case here, but apparently some cars can unlock automatically if the key is nearby. To hack this, you only need a sensitive receiver that can retransmit the signal from the key, and you need two people, on in proximity to the key, and another nearby the car when it unlocks.

That's not really the case. Some of them unlock via low frequency RF, but to my knowledge they still use encryption that uses their button click count as one of the variables plus a shared secret.

Yes, but the point of this scheme is that the car "believes" the key is in close range. If that is enough to get it to open the car, the thieves don't have to break any encryption, they just need to relay the RF signal. The faulty assumption on the part of the car manufacturers is that "RF signal present" equals "keyfob nearby".

Re: How some thieves broke into my car and why you're vulnerable too

#15

Post by ergoproxy »

My car was parked at the grocery store during an electrical storm. Lighting hit nearby and my "keyless entry system" unlocked the doors. After that my key fob no longer opened the doors. In the next few weeks I noticed more odd behavior: My dad's key fob opened my doors, my sister's key fob opened my doors, and a couple of random stranger's key fobs opened my doors. I've had the dealership reset my security system three times now at $40 a pop, and it still don't work right. Great technology! I long for the days before keyless entry technology, when you had to use a key to open the doors.

Re: How some thieves broke into my car and why you're vulnerable too

#16

Post by emidln »

gnaffle wrote: post #14
emidln wrote: post #11

Earlier quoted context omitted.

That's not really the case. Some of them unlock via low frequency RF, but to my knowledge they still use encryption that uses their button click count as one of the variables plus a shared secret.

Yes, but the point of this scheme is that the car "believes" the key is in close range. If that is enough to get it to open the car, the thieves don't have to break any encryption, they just need to relay the RF signal. The faulty assumption on the part of the car manufacturers is that "RF signal present" equals "keyfob nearby".

No system I've been exposed to was defeated by a simple replay attack. You needed the shared secret and the click count (plus proprietary algorithm), which would be incorporated into the OTA message. Most LF systems are pretty low-bandwidth as well, and lock out quite quickly.

Re: How some thieves broke into my car and why you're vulnerable too

#17

Post by gnaffle »

emidln wrote: post #16
gnaffle wrote: post #14

Earlier quoted context omitted.

Yes, but the point of this scheme is that the car "believes" the key is in close range. If that is enough to get it to open the car, the thieves don't have to break any encryption, they just need to relay the RF signal. The faulty assumption on the part of the car manufacturers is that "RF signal present" equals "keyfob nearby".

No system I've been exposed to was defeated by a simple replay attack. You needed the shared secret and the click count (plus proprietary algorithm), which would be incorporated into the OTA message. Most LF systems are pretty low-bandwidth as well, and lock out quite quickly.

To clarify, I'm not talking about a replay attack. It's a _relay_ attack where they use the RF signal transmitted by the actualy car/key, just over a bigger distance than you would normally expect.
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