6 ms·

But if an attacker owns the touchscreen, they can do nefarious things like adding a "Please re-enter your PIN on the touchscreen to confirm your purchase" dialo

by btown 4y ago

But if an attacker owns the touchscreen, they can do nefarious things like adding a "Please re-enter your PIN on the touchscreen to confirm your purchase" dialog, then match that PIN against a separate leaked database of card numbers and user identities. It's not just whether the card reader can be pivoted to; it's the entire notion that the kiosk itself carries the trust of the overall brand.

Gigachad 4y ago
It would be a huge amount of work to pull this off and it's something that would be detected within the day because its so odd and not at all how normal payment flows work. Not clear how you would match the pin either without having some personal info on the user which you don't have.
- alonsonic 4y ago
  Exactly. The kiosk app that communicates to the terminal only gets a "transaction approved" response. There is no personal identifiable information provided to the kiosk app so there would be no way to link the pin they typed in the kiosk back to the customer identity or card number. In short, for the kiosk this is a anonymous transaction that was confirmed paid. The most you could do is ask for more details in the kiosk app which would be clunky and very suspicious.
BoorishBears 4y ago
You could also tape a piece of paper up with a fake (tech support/tax help/credit help/reverse mortgage) line with a fake McDonald's endorsement in the early hours of the morning and make off with plenty of victims as the senior crowd rolls in for a grand time investment of 60 seconds. If you want to get creative with attacks you can, but sometimes comparing a creative attack to a "boring" attack can help frame the conversation. I've written kiosk apps that landed across the US and while there was a ton of hand wringing about security, and in an informal setting I brought up a simple question: If you reverse engineer the update process to have it show a penis, or you just carve a penis into the public display with a pocket knife, what's the difference and which is more likely to happen?
- franga2000 4y ago
  If an attacker can take control of the update process, they can push a penis-showing (or actually dangerous) update to all the machines in the network. That could be hundreds or thousands! Good luck doing that with a pocket knife. Also, vandalism is about the least interesting reason to hack kiosks. It can get you into an otherwise inaccessible network, which often contains all sorts of internal services with loose or no authentication (POS software often uses default creds because "it's on an internal netwok anyways"). Hacked kiosks are also often used as proxy servers for illegal activity and bots in DDoS botnets.
  - BoorishBears 4y ago
    Did you read the article? This is about security on-device The update process can be backed on the kiosk side, hacking the remote side of the update process is a completely different story. I mean in some cases that was a simple signed package hosted on an S3 bucket... how are you going to leverage that to vandalize a network of devices? And the kiosks are never on an interesting network (if they were there's dozens of ethernet ports scattered about the place you can use to get access anyways) Hacked kiosks being used as proxy servers when you need physical access to hack is also a very uninteresting problem. Why risk tying your physical self to a bot for nefarious usage when there are a million and one other "IoT" devices you can pwn instead?
- tinus_hn 4y ago
  It’s the old joke of listening in on the McDrive intercom after putting up a sign saying ‘the microphone is acting up, please yell’
naugtur 4y ago
If you can match a pin to a database of cards numbers, I can supply you with a database of all pins in existence
- sandworm101 4y ago
  Damn. How many bitcoins did you spend on that leak?
  - sgjohnson 4y ago
    for (i = 0; i <= 9999; i++) { ... }
    - sandworm101 4y ago
      Glad to see that my 6-digit pin is safe from hacking for at least a few more years.
      - bomdo 4y ago
        Don't be so sure of that. If your PIN just happens to start with 00, it is fairly trivial to jury-rig a common 4-digit hacking device to crack your 6-digit PIN.
        sgjohnson 4y ago
        jerry-rig*
        pliny 4y ago
        https://en.wiktionary.org/wiki/jury-rig https://en.wiktionary.org/wiki/jury-rig
        O__________O 4y ago
        eggcorn, acorn, all the same, just a different name: https://en.m.wiktionary.org/wiki/eggcorn https://en.m.wiktionary.org/wiki/eggcorn

by btown 4y ago

Gigachad 4y ago

It would be a huge amount of work to pull this off and it's something that would be detected within the day because its so odd and not at all how normal payment flows work. Not clear how you would match the pin either without having some personal info on the user which you don't have.

alonsonic 4y ago
Exactly. The kiosk app that communicates to the terminal only gets a "transaction approved" response. There is no personal identifiable information provided to the kiosk app so there would be no way to link the pin they typed in the kiosk back to the customer identity or card number. In short, for the kiosk this is a anonymous transaction that was confirmed paid. The most you could do is ask for more details in the kiosk app which would be clunky and very suspicious.

BoorishBears 4y ago

You could also tape a piece of paper up with a fake (tech support/tax help/credit help/reverse mortgage) line with a fake McDonald's endorsement in the early hours of the morning and make off with plenty of victims as the senior crowd rolls in for a grand time investment of 60 seconds. If you want to get creative with attacks you can, but sometimes comparing a creative attack to a "boring" attack can help frame the conversation. I've written kiosk apps that landed across the US and while there was a ton of hand wringing about security, and in an informal setting I brought up a simple question: If you reverse engineer the update process to have it show a penis, or you just carve a penis into the public display with a pocket knife, what's the difference and which is more likely to happen?

franga2000 4y ago
If an attacker can take control of the update process, they can push a penis-showing (or actually dangerous) update to all the machines in the network. That could be hundreds or thousands! Good luck doing that with a pocket knife. Also, vandalism is about the least interesting reason to hack kiosks. It can get you into an otherwise inaccessible network, which often contains all sorts of internal services with loose or no authentication (POS software often uses default creds because "it's on an internal netwok anyways"). Hacked kiosks are also often used as proxy servers for illegal activity and bots in DDoS botnets.
- BoorishBears 4y ago
  Did you read the article? This is about security on-device The update process can be backed on the kiosk side, hacking the remote side of the update process is a completely different story. I mean in some cases that was a simple signed package hosted on an S3 bucket... how are you going to leverage that to vandalize a network of devices? And the kiosks are never on an interesting network (if they were there's dozens of ethernet ports scattered about the place you can use to get access anyways) Hacked kiosks being used as proxy servers when you need physical access to hack is also a very uninteresting problem. Why risk tying your physical self to a bot for nefarious usage when there are a million and one other "IoT" devices you can pwn instead?
tinus_hn 4y ago
It’s the old joke of listening in on the McDrive intercom after putting up a sign saying ‘the microphone is acting up, please yell’

naugtur 4y ago

If you can match a pin to a database of cards numbers, I can supply you with a database of all pins in existence

sandworm101 4y ago
Damn. How many bitcoins did you spend on that leak?
- sgjohnson 4y ago
  for (i = 0; i <= 9999; i++) { ... }
  - sandworm101 4y ago
    Glad to see that my 6-digit pin is safe from hacking for at least a few more years.
    - bomdo 4y ago
      Don't be so sure of that. If your PIN just happens to start with 00, it is fairly trivial to jury-rig a common 4-digit hacking device to crack your 6-digit PIN.
      - sgjohnson 4y ago
        jerry-rig*
        pliny 4y ago
        https://en.wiktionary.org/wiki/jury-rig https://en.wiktionary.org/wiki/jury-rig
        O__________O 4y ago
        eggcorn, acorn, all the same, just a different name: https://en.m.wiktionary.org/wiki/eggcorn https://en.m.wiktionary.org/wiki/eggcorn