Can anyone tell me why this isnt complete bollocks

[dennis]

Rubbish. Good job you don't do security as you don't understand the problem in the first place.

[dennis]

More rubbish from someone who hasn't understood the problem and is trying to look like he does.

[mb07jeb]

[mb07jeb]

[Steve Walker]

GMP have been warning people about a spate of thefts from (not of) cars with keyless entry in the local area in the last few days.

The car fobs that you press a button to operate use a rolling code system to prevent the recording of a code as it is used and subsequent playback.

I think that vulnerabilities in the rolling code system have been found though.

SteveW

[Bob Eager]

My car unlocks when you touch the inner part of a door handle, as long as the key is within a metre of the car.

The engine won't start unless the key is physically inside the car.

[Steve Walker]

That works for fobs where you press a button to disarm and unlock and is indeed the sort of system that is used; but with keyless entry systems they simply relay the communication between the car and the key over more than its usual range, so they are using the real fob at the time that they break in and need no knowledge of the codes at all. Neither the car nor the fob have any way of knowing that they are not in close proximity.

SteveW

[Steve Walker]

The car transmits all the time and the key responds when it receives a request from the car, so little power drain.

Normally the fob muust be pretty close to the car and it might well be possible to power it from the signal it receives.

SteveW

[Bill Wright]

A flat plate on one site of the tx will not prevent transmission.

Bill

[Bill Wright]

With conductive bonding all the way round the lid. Any slit or slot or other discontinuity will let RF through. I have a van with no rear windows and a metal bulkhead and RF gets into the back with no trouble.

Bill

[Bill Wright]

Can't do. It would run the battery down. They must receive a signal from the car.

Bill

[Bill Wright]

I just tested this. Put my phone in a biscuit tin and rung it up. It worked. Sounded funny though!

Bill

[Andy Burns]

Place a jammer near the car, so car doesn't receive properly, use a device to capture code n from the remote, user notices car doesn't open, presses button again, device captures code n+1, disable the jammer, play back code n, car opens, thief keeps code n+1 for later use ...

car and remote allow a 'window' of several rolling codes, so in practice thief can capture n+2, n+3 etc codes ...

[misterroy]

I wrapped a phone in aluminium foil and called it. It did not ring. Took it out and tested again and it did.

[misterroy]

A friend came unstuck when he drove his wife to work and then stopped at a beach on the way home. She had the electronic key in her handbag. He could not start the car again and had to make his way to her work in slippers and a dressing gown.

[Harry Bloomfield]

Bill Wright explained on 15/07/2018 :

I wasn't suggesting it would. My wallet is a back pocket folder, the height of notes, but when the wallet is folded the notes are folded, as is the foil. The foil is the full size of my wallet when open and inserted in the outer note compartment.

Folded and in my pocket, my cards are tightly sandwiched on both sides by foil. Does that explain it better?

[Jack James]

Not with a rolling code system they can't.

[Harry Bloomfield]

on 15/07/2018, Bill Wright supposed :

But both the incoming RF and the outgoing RF response will be greatly diminished. Here we are dealing with already very weak signals. In the push button car remotes, with some cars you need to be very close to the car, to get the car to respond. Range with current car is exceptional, I can manage 100yds in good conditions.

[Harry Bloomfield]

In the same test with both a mobile and a wireless landline phone, both failed to ring. A similar test with cooking foil, produced the same result. My wireless landline's base is located at a high position in the house, so as to provide coverage right out to the back of the garden, which it does - except it fails in the garage and fails in the caravan.

The caravan has a metal roof, metal sides, composite front and rear panels. My garage has a metal roof.

Your TV antenna coax is only screened by a wire mesh in the older coaxes. Modern, better ones include both the mesh and a copper foil.

Try wrapping your ignition key in cooking foil, inserting it in the ignition lock and starting the car.. Tell me whether it starts?

[Harry Bloomfield]

alan_m brought next idea :

So look around you before opening your wallet, I do..