Comment by mystraline

4 months ago

Yeah, TPMS and the way its implemented is a BAD idea.

1. Data is not signed.

So data can be easily spoofed and jam up the real sensor's transmissions.

2. Serial number is not obfuscated or in a reduced serial number set.

This allows TPMS trackers to be placed at high vehicle through areas and uniquely track cars. Is dying out due to Flock and ALPRs.

3. Some cars, primarily luxury, will force slow you down to 15mph, honk horns, and go into limp mode.

Note this is trusting unencrypted, unsigned, cleartext data. This is a terrible idea, and you cant turn it off.

> 3. Some cars, primarily luxury, will force slow you down to 15mph, honk horns, and go into limp mode.

I'm surprised some company hasn't sold a "gun" to law enforcement that will disable cars remotely this way.

  • TPMS data is "questionable" enough already that no OEM is using it's sudden disappearance as a key do to anything drastic.

    I can see them doing it if the data goes from good to bad and then the bad persists over a key off cycle though.

    • Its not disappearance.

      Look at what happens if you spoof and spam a 0kPa event on various cars.

      Some show a tpms warning. Some luxury ones do limp mode.

This is no different than the internet, really. "Hey, we made this thing to operate in a safe environment." Years later: "Oh, crap, what do you mean it needs to be secured?"

> 3. Some cars, primarily luxury, will force slow you down to 15mph, honk horns, and go into limp mode.

Source? I can't find any reference. It looks like you're hallucinating.

  • Ah, the new AI insult.

    Nah, I'm not providing exploit code to something unpatchable.

    But if you use a rtlsdr, read, decode, modify, and then use a Hackrf to generate the waveform... Yeah, it works.

    No ai. No hallucination. Just good at signals.

    • A link to any article/manual/reference about this vehicle response to low tire pressure would be enough... if it exists, surely the manufacturers would have documented it.

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