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ATM Hack Gives Cash On Demand

Posted by samzenpus on from the one-card-bandit dept.

angry tapir writes "Windows CE-based ATMs can easily be made to dole out cash, according to security researcher Barnaby Jack. Exploiting bugs in two different ATMs at Black Hat, the researcher from IOActive was able to get them to spit out money on demand and record sensitive data from the cards of people who used them. Jack believes a large number of ATMs have remote management tools that can be accessed over a telephone. After experimenting with two machines he purchased, Jack developed a way of bypassing the remote authentication system and installing a homemade rootkit, named Scrooge."

14 of 193 comments (clear)

  1. Interesting Hacks... by nosferatu1001 · · Score: 5, Interesting

    Originally delayed to let the companies patch. Interested to see if he can live up to his claims to be able to find similar issues in other brand ATMs as well.

    1. Re:Interesting Hacks... by silentcoder · · Score: 4, Interesting

      That reminds me. A couple of Christmas's ago I was visiting my sister in a small rural town where she lived at the time. Wanted to go draw cash at one point so walked down the main road to the town's only ATM - run by local bank ABSA (yeah - not afraid to mention it). My own bank not having an ATM in town this was the only choice available.

      As I stepped up to it... the interface was obscured by a warning message:
      F-Secure Anti-Virus for Windows has detected a virus in file ...

      Floating around.

      Being aware that
      1) This bank's ATM's run windows
      2) They use F-Secure for virus protection
      3) It obviously is connected in such a way that it can still GET infections

      I turned around, bummed cash of my sister and paid her bank online - there was just no way I was going to stick my card in that ATM. I am also really glad I'm not a customer of that bank - and despite the nearest ATM to my house being run by them - never use their ATM's - I would rather spend the bit of extra fuel and drive to my own bank (which may not be better - but at least I haven't seen with my own eyes that it's THAT bad). Besides the service charge saving I suspect outweighs what I spend on fuel so it's worth it either way.

      --
      Unicode killed the ASCII-art *
    2. Re:Interesting Hacks... by blisteringsilence · · Score: 5, Informative

      Disclaimer: I own about 30 of these machines, and work as a repair tech for a statewide area. It's a nice side income. Let's start at the beginning. This hack requires that a machine be connected to the outside via phone. This is increasingly going away. I would guess that 40% of the machines I work on are connected via internet now, as opposed to 15% a year ago. My first comment is that the remote management software that is being exploited isn't turned on in the vast majority of the machines that are out there. Whether it's triton connect, or tranax's remote access, all of the processors that I've encountered require that it be disabled for the machine to work. This software was important 4 or 5 years ago from a machine management standpoint, but with realtime internet tracking of machine status, there's just no reason for it to be enabled. Now, as to the comment about keys not being unique per device: A key on an ATM opens two areas: the "computer" module on top of the safe, and the bit of plastic that obscures the safe dial. A service technician (like me) is most of the time a freelancer who's in this for some side cash. When I go to a customer's location, my goal is to fix the problem and get out. As I almost never need to get to the vault of the machine, I have a keyring that has the standard sized keys for all of the machines I work on. An access password or vault combination can be obtained by a call to the owner of the machine. A unique key, however, cannot. Moreover, as many older machines require access to the processing unit in order to fill the machine (you have to hit a physical button to get into that menu), you have to make it easy for your armored service to access the top as well as the vault. It's unreasonable to expect a vaulting company to haul around 60 or 70 keys to fill the machines that they have on their list for that day.

    3. Re:Interesting Hacks... by blisteringsilence · · Score: 4, Interesting

      But does that really help matters any? wouldn't being connected to the internet be even MORE risky? surely the same "dial-in" access is still there, just over TCP/IP instead of dialup, and with exposure to the internet you have even more capacity for abuse by millions of hosts.

      Maybe yes, maybe no. The first part of this answer is that when you're connected to the internet, you remove the bandwidth problem of a modem connection. AND, because you're not tying up a phone line anymore, you have more flexibility with your communications.

      So, machines that are hooked in via TCP/IP do not have the option to accept remote connections initiated from anywhere other than the machine. The communication HAS to start with the machine, and the data is encrypted 19 ways from Sunday. To start with, you have the master keys that allow the machine to communicate with the processor. After they are input, they're encrypted and stored in epoxy buried chips in the keypad, and any interruption of electrical power to those chips (which runs through fry wires from a battery also stored within the epoxy matrix) kills the keys.

      So your communication starts with the machine opening a connection with a dedicated IP server on one of 3 possible ports. During handshake and authentication a unique time-based one time key is transmitted back to the machine. This super-encrypts the keys, which are then sent, followed by the transaction information, and the transmission is closed out. These machines are also usually programmed to auto-connect every 15 or 30 minutes with a machine status update (thereby eliminating the need to dial in remotely).

      Now, as all this information is going out over the general internet, it's possible to intercept the packets, but I don't know what good they'd do for you, as there's no way to get to the original master keys assuming you could get past the super encryption, thereby securing the first level.

      Now I work as a tech for a local telco, and the ATM machines I've worked with have mostly been connected by ADSL, but my understanding was that although it was still a TCP/IP connection, they were actually on a special logical connection back to the bank that kept their data away from the internet? wouldn't this make more sense? (from the stand point of a telco tech, these machines do not connect to our usual DHCP servers, and I believe their entire logical connection is separate, though what the end point is I don't know as I don't handle that end of the connection)

      The machines that are located at gas stations and bars and whatnot use a standard internet connection. The only requirement is that the location has to have a static IP. You have to remember, these machines only cost $2K - $5K, and the owner only makes $100 - $500 per month on the machine. Not to mention, they're not doing that many transactions.

      Would the solution you propose make more sense? Absolutely. But it's cost prohibitive, and beyond the scope of 99% of the owners, and 75% of the service techs. If these proposals were to be codified, you'd see fees go through the roof to make up the difference.

      Also:

      ...and the ATM machines I've worked with...

      Pet peeve.

  2. I see what you did there... by fuzzyfuzzyfungus · · Score: 4, Funny

    This is clearly just a slashvertisement for Microsoft's expansion of their "Cashback" promotion from Bing to WinCE "The Product that Needs it More Than Bing"...

    Editorial standards these days... I ask you...

  3. Pretension by aliddell · · Score: 5, Funny

    Exploiting bugs in two different ATM machines

    'ATM machines'? Really?

    --
    What do you think, sirs?
    1. Re:Pretension by Spad · · Score: 4, Funny

      And he didn't even need a PIN Number

    2. Re:Pretension by RulerOf · · Score: 5, Funny

      Rumor has it that if the hacker can find the MAC controller address for the NIC card in the ATM machine, he can use specially crafted TCP/IP protocol and also expose your SSN number.

      --
      Boot Windows, Linux, and ESX over the network for free.
    3. Re:Pretension by need4mospd · · Score: 4, Funny

      But only ATM machines with specific UPC codes and LCD displays will do this. And you should make sure your PC computer has enough RAM memory and is setup to run on AC current using only RF frequencies to communicate. Always back up these transactions to a DAT tape or CD disks. If you do this right, you should be able to avoid any VAT taxes so you can afford more KFC chicken.

  4. Re:Really? by Pharmboy · · Score: 5, Interesting

    There is at least one precedent for making owning machines illegal. Slot machines are regulated and it is illegal to own one in most states, even if the coin mechanism is disabled to play for free. Of course, that is what makes them l33t to own for rich folks. Kinda like Coors beer in "Smokey and the Bandit", you want it because it is illegal.

    --
    Tequila: It's not just for breakfast anymore!
  5. Re:Redundancy by prionic6 · · Score: 4, Funny

    But who makes the ATMMs?

    It's machines all the way down!

  6. Re:Really? by zigziggityzoo · · Score: 4, Interesting

    I know of a couple of restaurants that have their own ATMs with a "cash only" policy for acceptable payments. Anyone without cash is directed to the ATM they own. Instead of it costing them a percentage to accept cards, they make money off the ATM.

    --
    Zing!
  7. Re:Patchless ATM "hack" by BrokenHalo · · Score: 4, Interesting

    Debit and credit cards are OK so long as you are a bit careful about not where you use them and not letting them out of your sight (in order to to skim them), and check your accounts reasonably frequently. They are certainly better than cheques.

    Banks will often not even look at a signature on a cheque, let alone make any attempt to verify it. As an example, I once accidentally grabbed my wife's chequebook and used it (signing my own name) to purchase goods. I realised my mistake a couple of days later and attempted to go into the shop to replace my presumably dodgy cheque with cash, but the bank had already paid up on it. Now in this case, it was an honest enough mistake, but it has made me a lot more careful about where we store our chequebooks since.

    At least with credit cards, there is always the option of a chargeback.

  8. Re:Why go through all that trouble of hacking? by blisteringsilence · · Score: 5, Informative

    The store owner buys or leases the machine. However, they don't change the default service password that's listed in the owners manual. A manual you can buy on line.

    Well, I guess if I'm going to criticize, I'll start here. No PCI-compliant machines allow you to go through the configuration process without inputting 3 different levels of new password. The attack you describe above might have worked 2 years ago. No longer. Sorry. And you don't have to buy the manual, they're (mostly) available for free.

    There have been several incidences of someone coming into a small store, typing in the series of key presses to get to the service menu, entering the default password, and wham, the machine gives them all the cash! It's quick and easy with no messing hacking necessary.

    No there haven't. The only exploit that could be executed in person was the following:
    1. Thief buys prepaid $200 visa card with PIN.
    2. Thief accesses the service menu of the machine (using default or socially engineered password).
    3. Thief changes the machine's internal systems to think it's holding $5 bills instead of $20 bills.
    4. Thief exits service menus.
    5. Thief puts in card and withdraws $200. Since the machine thinks it's holding $5's, it dispenses 40 total $20 bills ($800). The thief makes off with a net of $600.

    However, this exploit is no longer possible, as the master keys that allow an ATM to communicate with the processor are now erased when you change the denomination of bills the ATM dispenses.

    The process you describe has never worked. There is an option in a service menu called "test dispense," but it kicks the bill into the reject bin, not into the cash pickup.

    Please try again.