Comment by dmpanch
2 years ago
I work for a company that manufactures access control and communication systems. The readers we develop support a variety of ID standards, from unencrypted EM-Marin and a long time ago cracked Mifare Classic to modern Desfire EVx standards. According to our statistics, more than 95% of customers still continue to use the most insecure identifiers because of their low cost and ease of operation.
Many of the installed devices are not properly maintained, even if the manufacturers continue to support them, because you have to pay for maintenance. In addition, not all equipment can be updated remotely over the network or even have a network connection to do so remotely.
Even if your cards are encrypted, it still can't guarantee you protection, because in most cases card readers are connected to controllers (not in the case of all-in-one devices like this lock) via Wiegand protocol, which doesn't provide any data encryption, so the identifier ID is transmitted over two wires in the clear form.
At some point, isn't there some responsibility that rests with manufacturers for choosing to continue to support known-insecure standards?
How many browsers do you think support the TLS_NULL_WITH_NULL_NULL cipher?
> At some point, isn't there some responsibility that rests with manufacturers for choosing to continue to support known-insecure standards?
There should be. Also there should be liability for access control system customers for choosing low cost, insecure solutions. But just like in the InfoSec world, there are simply no consequences to companies that cheap out and fail at security. These companies just issue a press release saying “we take security very seriously” and continue on with their business.
It's often a compatibility thing too. Insecure standards can often coexist because they're the lowest common denominator. It's just a "password" stored and transmitted as plaintext.
A secure system would involve a PKI which increases complexity and management overhead significantly (you won't be able to just copy "passwords" from one system to another, etc).
Compat is a factor and valid in some instances. It's not valid at all in this case. The old systems are wholly insecure, and should not be offered at all.
This is just some faceless corp being cheap and ignoring the consequences, not their problem.
Browser manufacturers normally don't have contracts that binds them to supply product X for Y years.
Heh, You mean IE6 and ActiveX controls :D
I think the only reason why we have the amount of attention to security that we do in the software industry is because Internet enabled cheap automated large-scale attacks - enough so that even very low-value targets are well worth it.
I'm in a similar space and a lot of our customers continue to use old-school Wiegand low-frequency badges even though they're ridiculously vulnerable to replay attacks to the degree that Flipper Zero has automated it.
For a while I've had a question about hotel keycard technology, maybe you can answer.
Essentially every time I've stayed in a hotel with contactless keycards (usually in a group needing 3-5 rooms for 2-3 nights) at least one person has needed to get a keycard reissued.
What's up with that? My workplace's smartcards and my contactless bank cards keep working for years on end.
Hotel keycards usually work by having dynamic data written to them at the front desk (as the locks are often not network connected, at least in older systems, so they write things to the card like "works for room 123 until March 30th noon and the gym" or "works for room 456; sequence number 2, invalidate all prior keys").
There are two types of magnetic stripe cards available: High-coercivity (HiCo) and low-coercivity (LoCo). The field-rewritable kind used in hotels is usually LoCo, to make the writers smaller and cheaper. But that also makes the cards much more prone to accidental corruption by magnets you might have on you, like earbuds, magnetic wallets etc.
Bank cards are usually only ever programmed once (these days), i.e. when they're issued, so they're usually HiCo, making them much more robust against that. In addition to that, magnetic stripe usage has been phased out for payment cards in most countries and is getting rare even in the US, so for all you know, and depending on where you live/shop, your magnetic stripes might have already been demagnetized without any adverse effects!
Bonus trivia question: Guess which kind NYC MTA Metrocards are :)
Edit: Oh, I just saw that you asked about contactless keycards! For these I actually have no idea, and I haven't had one fail on me yet.
I just know that they often use a similar scheme ("works for rooms x, y, z, until timestamp n"), sometimes with a bit of cryptography on top (often with a single shared key across all instances of the same lock and even across hotels...) but using non-networked locks, so there can definitely be synchronization/propagation issues too.
I used to work as maintenance on a big chain hotel and we had magstripe card locks, I don’t think strong security is their primary goal as in a hotel the staff can enter any room at any time, the cards me and my team had were “god mode” we could open any door at any time even when locked from inside. If the lock didn’t work “firmware problems, dead batteries, stuck mechanism” we had another device that worked by removing a cover and connecting with a wire, this was also used for testing and FW updates.
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Shouldn't that be other way around? Keycard only holding the simple numeric id, which is burned into silicone chip on it and impossible to modify, and the reader at the door, connected to hotel central system checks what privileges that particular keycard grants?
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> Guess which kind NYC MTA Metrocards are :)
None anymore! They're being phased out as we speak. They were supposed to be end of life last year, though they pushed back end of life EoY 2024, because the MTA is never on time, all the time.
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At least with old fashioned keys you can't easily give out a duplicate. I was once in bed, late at night, lights out, when someone let themselves into my room - a rather drunk guy demanding to know what I was doing in his room. The desk clerk had got his room number wrong and given him another card to mine. It all worked out OK, but under other circumstances I could imagine that it might not.
> What's up with that?
It was programmed incorrectly and expired before it should have.
The stay was extended but the key was not updated with the new departure date.
A new key was erroneously issued for the room, someone used the new key to go into the room, saw someone was already staying in the room, and had to get keys for a different room. This would cause all old keys to stop working since every time a lock sees a new key used, it assumes a new hotel guest is staying.
Or it lost its data for whatever reason.
My brain was ANDing the first three paragraphs until I got to the OR in the last paragraph, wondering why in the world those otherwise discrete scenarios would have a combinatorial effect. I'm wired to look ahead to determine AND versus OR with a comma-delimited series, but not with a paragraph-delimited series. It's a cool pattern but very unexpected, and I'm not sure you could successfully tack on other thoughts before or after the series, because what would delimit those from the series without overloading the meaning of a paragraph separation?
Given a need for multi-sentence items within a series, I go for bullet points. Hyphen character to start each point if no rich UL formatting is available.
there you go. make a fake coil card and tell the door you're staying for 25 years and a new guest ...get in and own the room
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I had the same experience with NFC hotel card failing after being in my pocket (next to other cards and a phone). It had to be re-programmed at the hotel's desk to work again. Puzzled me enough to search net for the answers, but to no avail.
It's the phone. Have had this happen multiple times with just the card and my phone. Not sure if it's doing some kind of NFC ping on the phone or if there's just enough of a magnetic field around it or what, but I reliably locked myself out of my room the first week doing field work this year by putting my phone and my hotel card in the same pocket.
Same as basically any physical lock can be trivially picked. Yet no one is buying office door locks based on pick-resistance. Burglars will smash their way in anyways.
>Even if your cards are encrypted, it still can't guarantee you protection, because in most cases card readers are connected to controllers (not in the case of all-in-one devices like this lock) via Wiegand protocol, which doesn't provide any data encryption, so the identifier ID is transmitted over two wires in the clear form.
It is true, seems like probably better to go back to keys and lock.
Unfortunately most physical keys also transmit their bitting in the clear
> so the identifier ID is transmitted over two wires in the clear form.
I'm much more worried about someone using to a clothes hanger looking tool [1] to break into my hotel room than someone exposing cables and reading data over the wire to unlock the door.
[1] https://www.youtube.com/watch?v=-3G9pyvCBcM