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Drivers locked out of their cars at Royston Tesco

bbc.co.uk

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Re: Drivers locked out of their cars at Royston Tesco

#31

Post by wallaBBB »

I highly doubt it's actually jamming the the 433MHz signal from the fob. Command signals are most likely properly decoded by the vehicle, but rather the RSSI measurements are getting disturbances. Those signals are LF (25kHz or 125kHz)sent from the vehicle (multiple antennas) to the fob for localization. Fob performs the measurements and returns values to the vehicle. If the fob is not localized in the expected area, passive unlock or start would not work, and could even start the alarm.

Some gate/card readers going crazy maybe...

Wireless chargers that now come inbuilt as standard can also create enough disturbances to mess up the LF RSSI (but limited to single vehicle). Manufacturers are slowly moving to UWB and BLE for localization, as ToF is more robust (especially for relay attacks) than a simple signal strength measurement, plus it provides a common mechanism for both phones and fobs on the vehicle side.

Re: Drivers locked out of their cars at Royston Tesco

#32

Post by jsmith99 »

globular-toast wrote: post #24
jsmith99 wrote: post #21

Earlier quoted context omitted.

Great way to get lynched by angry drivers assuming the person with the gear is the culprit.

It's in Britain. We're not like that.

The shame of being angrily tutted at is comparable.

Re: Drivers locked out of their cars at Royston Tesco

#33

Post by grey-area »

tmhrtly wrote: post #17
cube00 wrote: post #11

> ask to speak to the on-duty manager to make them aware you are having difficulties getting into your vehicle as they are aware of the process to follow. Wonder what the "process" to solve this is if they don't even know the cause?

Portable faraday cage over the car and driver?

I wonder if a cone of tinfoil (handily available at Tesco) would work, shielding key and lock during unlock? Or are the receivers elsewhere in the car?

Re: Drivers locked out of their cars at Royston Tesco

#34

Post by gnfargbl »

cube00 wrote: post #11

> ask to speak to the on-duty manager to make them aware you are having difficulties getting into your vehicle as they are aware of the process to follow. Wonder what the "process" to solve this is if they don't even know the cause?

I would bet a small amount of money that the process is (1) put the fob very close to the car's receiver and try again, followed by (2) disassemble the fob and look for a mechanical key.

Re: Drivers locked out of their cars at Royston Tesco

#35

Post by l33tman »

hcho wrote: post #29
ed_balls wrote: post #22

Earlier quoted context omitted.

Does such car exist? (Tesla Maybe?)

None of the cars I have driven in the last decade had physical keys. Owned a Nissan, Mercedes and Toyota, rented various BMWs, Peugeots etc...

In the keyfob there is usually a foldout key hidden even in modern cars

Re: Drivers locked out of their cars at Royston Tesco

#36

Post by zulln »

hcho wrote: post #29
ed_balls wrote: post #22

Earlier quoted context omitted.

Does such car exist? (Tesla Maybe?)

None of the cars I have driven in the last decade had physical keys. Owned a Nissan, Mercedes and Toyota, rented various BMWs, Peugeots etc...

A lot of them actually have a real key "hidden" within the digital fob, see example: https://www.bimmer-tech.net/blog/item/105-about-bmw-key-fob

I have never had to actually use it, but looked into it when I got low battery-warnings to make sure I would not be locked out.

Assuming this is not a legal requirement I am sure there are models where this is not possible though.

Re: Drivers locked out of their cars at Royston Tesco

#37

Post by gmueckl »

ed_balls wrote: post #22
neals wrote: post #13

Earlier quoted context omitted.

Cars not having physical locks on doors or for ignitions anymore is one, I assume.

Does such car exist? (Tesla Maybe?)

My car has only has a mechanical lock on the driver's door. And the manual strongly advises against regular use of that lock for some reason. Supposedly, it is just a backup. A quick search of other brands comes up with similar stories and anecdotes of these locks breaking quickly if someone was relying on then too much.

Re: Drivers locked out of their cars at Royston Tesco

#38

Post by WJW »

nom wrote: post #19
cube00 wrote: post #11

> ask to speak to the on-duty manager to make them aware you are having difficulties getting into your vehicle as they are aware of the process to follow. Wonder what the "process" to solve this is if they don't even know the cause?

maybe they bring out the huge car sized faraday cage

If you build a structure out of supermarket trolleys around the car, would that be sufficient? I love the idea of a car size foldable Faraday cage btw.

Re: Drivers locked out of their cars at Royston Tesco

#39

Post by 05 »

Nextgrid wrote: post #10
londons_explore wrote: post #3

It'll be someone using a 'jam, listen, and replay' device to unlock and start keyless cars so they can drive them to a port and steal them. Pretty much every week a car is stolen this way from my street. I now always take the engine management fuse out of the fusebox when parking my car so at least the car can't start when a thief pulls this... They tried anyway though!

Curious as to how such a device would recover the original signal while it’s broadcasting a stronger signal to jam the frequency. Also, if you don’t mind, which city/country are you in? It seems insane that this is a regular problem happening in the same location and law enforcement doesn’t catch on.

a) use a directional antenna for the jamming transmitter. Everyone except the car can receive the fob signal just fine

b) use a directional antenna pointed at the fob. You jam everyone but RSSI for the fob signal received through the antenna is still acceptable

c) jamming signal triggered by fob transmission, possible to jam specific packet bytes, like the CRC (recoverable later)

d) jamming signal uses a period that is a little shorter than packet length, repeated packets can be recovered by combining their intact parts

etc..

Re: Drivers locked out of their cars at Royston Tesco

#40

Post by hcho »

l33tman wrote: post #35
hcho wrote: post #29

Earlier quoted context omitted.

None of the cars I have driven in the last decade had physical keys. Owned a Nissan, Mercedes and Toyota, rented various BMWs, Peugeots etc...

In the keyfob there is usually a foldout key hidden even in modern cars

None of the cars I owned had this. I hadn't fiddled with the rented cars keys so those might have had it.
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