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Trying Out Flipper Zero

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101–109 of 109 posts

Re: Trying Out Flipper Zero

#101
post #35

Earlier quoted context omitted.

Responsible disclosure exists for serious exploits, and it sort of works. Auto makers had ample time to learn that their current radio-operated locks are insecure by design. They had years while everybody even slightly interested knew e.g. how a replay attack can be done. Did they need any more responsible disclosure time in order to act? BTW there's no need to radically invent anything in that space; say, SSH offers…

Opening (and mobilising) a car is a vastly different scenario from opening an SSH session and your typical Mercedes or BMW driver is not your average SSH user. Customers want their cars to unlock on approach and they've become used to it. They expect the trunk to open when they swipe their foot under the tail bumper while they are holding their groceries in both hands. Keyless entry systems are useful and the most im…

A keyless system can use the kind of exchange with pre-shared keys which SSH uses (TLS uses a similar system). As I don't have to type a password when I ssh to a remote box with my key on it. a car user won't need to type anything, and even to press a button on anything.

That is, the current proximity-based keyless access would work the same, from the customer's POV: you're around and you have the key, the car grants you all access. You're away, and the car beeps and locks up.

It would just require somehow larger and more expensive components in the keyfob, which is anyway a rounding error compared to the price of the car. But, more importantly, it would require to make a fuss and change something in an area which "just works" now, which is always a hard and thankless task in a large corporation. Beside that, car manufacturers have little interest in making your car harder to steal (unless they look excessively bad compared to every competitor); they'll gladly sell you a new car instead.

Re: Trying Out Flipper Zero

#102
post #10

Earlier quoted context omitted.

Do those arguments really hold up though? I get that these devices are sort of the “messenger” in “don’t shoot the messenger”, but still. Security is about appropriate security. A general teenager or thief wanting to cause issues would not know what to do with an SDR and laptop, versus something like the Flipper making it point and click. So now that something is made so readily available, we need to increase the cos…

Many solution exist (rolling codes, encryption, tight timing etc.) that make it difficult to open a vehicle quickly. The main issue is that there are still cars being sold which might as well have no locks at all.

No locks means people are less likely to break the windows and leave a mess or get injured themselves.

Re: Trying Out Flipper Zero

#103
post #17

Earlier quoted context omitted.

>Is there an easy solution to improve locks on cars? Public/Private Keys? You know a secure protocol like SSH?

Doesn't help against a common attack possible for all reasonably modern luxury cars (which happen also to be the most interesting targets). For these cars it's enough that the key is near and it is considered a feature that no user interaction (like pressing a button on the keyfob) is required. This can be exploited by relaying the signal from the original key to an attacker who is near the car. Cryptography alone ca…

To defeat the relay attack, you need tight restrictions on time-of-flight. That restricts the allowable distance between the vehicle and the actual real key fob.

Re: Trying Out Flipper Zero

#104
post #101

Earlier quoted context omitted.

Opening (and mobilising) a car is a vastly different scenario from opening an SSH session and your typical Mercedes or BMW driver is not your average SSH user. Customers want their cars to unlock on approach and they've become used to it. They expect the trunk to open when they swipe their foot under the tail bumper while they are holding their groceries in both hands. Keyless entry systems are useful and the most im…

A keyless system can use the kind of exchange with pre-shared keys which SSH uses (TLS uses a similar system). As I don't have to type a password when I ssh to a remote box with my key on it. a car user won't need to type anything, and even to press a button on anything. That is, the current proximity-based keyless access would work the same, from the customer's POV: you're around and you have the key, the car grants…

I don't know if I understand you correctly but I don't see how this helps against a relay (not replay) attack.

"anyway a rounding error compared to the price of the car. But, more importantly,"

For car manufacturers rounding errors start many, many digits behind the decimal point. At their volume a cost down of a fractional cent is significant.

Re: Trying Out Flipper Zero

#105
post #56

Earlier quoted context omitted.

Wouldn't measurements of ping between keyfob and car be able to detect such attacks?

There are mitigations, my point was mainly that there is more to it than a implementing a tried and proven protocol but developed for a completely different use case (like SSH). Keyless entry systems are what they are because of a complicated trade-off between convenience, reliability, security and other factors and not necessarily because all engineers at car companies are idiots.

>convenience

True, if you don't care about security upload you password to the cloud or open your Car without any manual action ;)

Re: Trying Out Flipper Zero

#106
post #40

Earlier quoted context omitted.

Ah I don't imagine there are any physical stores by me that would stock this. That said I did a google search for "flipper zero site:cz" and it seems there's sometimes second-hand ones listed on ebay-like sites, so that's an option.

When I said store I meant online!

Oops, yeah that makes more sense :)

Re: Trying Out Flipper Zero

#108
post #10

Earlier quoted context omitted.

Do those arguments really hold up though? I get that these devices are sort of the “messenger” in “don’t shoot the messenger”, but still. Security is about appropriate security. A general teenager or thief wanting to cause issues would not know what to do with an SDR and laptop, versus something like the Flipper making it point and click. So now that something is made so readily available, we need to increase the cos…

> Is there an easy solution to improve locks on cars? Turn off keyless entry and use the mechanical key.

The challenge/response mechanism still occurs when using the key. Try opening most cars with a dead keyfob battery - on pretty much any recent car I've seen doing so triggers the alarms and turning the key in the ignition will not disarm the immobiliser.

Re: Trying Out Flipper Zero

#109

Earlier quoted context omitted.

For instance, car keys.

>For instance, car keys. Have you ever owned a push button start vehicle? It is a strictly superior UX.

Strictly superior? Dunno, not sure I'd call depending on some additional authentication widget that has a battery that dies every year or so strictly superior.

Doubly so when it's temperature sensitive, so most likely to strand you when you are very cold. If given the choice I'd rather have something that works for the life of the car instead of depending on a battery powered dongle.

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