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Shmoocon Demo Shows Easy, Wireless Credit Card Fraud

Sparrowvsrevolution writes with this excerpt from a Forbes piece recounting a scary demo at the just-ended Shmoocon: "[Security researcher Kristin] Paget aimed to indisputably prove what hackers have long known and the payment card industry has repeatedly downplayed and denied: That RFID-enabled credit card data can be easily, cheaply, and undetectably stolen and used for fraudulent transactions. With a Vivotech RFID credit card reader she bought on eBay for $50, Paget wirelessly read a volunteer's credit card onstage and obtained the card's number and expiration date, along with the one-time CVV number used by contactless cards to authenticate payments. A second later, she used a $300 card-magnetizing tool to encode that data onto a blank card. And then, with a Square attachment for the iPhone that allows anyone to swipe a card and receive payments, she paid herself $15 of the volunteer's money with the counterfeit card she'd just created. (She also handed the volunteer a twenty dollar bill, essentially selling the bill on stage for $15 to avoid any charges of illegal fraud.) ... A stealthy attacker in a crowded public place could easily scan hundreds of cards through wallets or purses."

24 of 273 comments (clear)

  1. Aluminum Foil in the Wallet by Anonymous Coward · · Score: 5, Funny

    That is why I have lined my wallet with the aluminum foil that I had left over from making my hat.

    1. Re:Aluminum Foil in the Wallet by cvtan · · Score: 4, Informative

      A Faraday cage need not be grounded. http://en.wikipedia.org/wiki/Faraday_cage

      --
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    2. Re:Aluminum Foil in the Wallet by FictionPimp · · Score: 5, Interesting

      I have a RFID blocking wallet. My security badge for work will not scan when inside the wallet (but it will scan inside all my co-workers wallets and my old wallet).

      Same price as a normal wallet and not a bad investment.

    3. Re:Aluminum Foil in the Wallet by _0xd0ad · · Score: 5, Informative

      Grounding a Faraday cage accomplishes two things:

      1) The cage is made from a conductive material. If a hot wire shorts against it, and you touch the cage, you could be electrocuted. Grounding it is therefore prudent.

      2) If anything inside the cage is trying to transmit, it turns the entire planet into its antenna. Your transmission is going to be pretty weak if you're trying to drive a planet-sized antenna with a few milliwatts of power. (Actually, no weaker than normal, but only if you're far enough away from the antenna that it looks like a point-source.)

      Note the significant absence of "prevents radio signals from getting into the Faraday cage". It doesn't. Grounding has nothing to do with preventing radio signals from getting into the Faraday cage. The cage's mesh diameter is the only factor that affects which radio signals can get into the cage.

  2. Re:Is this news? by Jeng · · Score: 5, Insightful

    It is news in that this has now been brought up to the credit card companies in a manner which cannot be easily ignored.

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  3. FUD by OverlordQ · · Score: 5, Insightful

    In fact, contactless cards do offer one security feature traditional cards don’t: Along with the card’s 16-digit number and expiration date, the cards are set to offer up a one-time CVV code with every scan. Those codes can only be used for one transaction, and have to used in the order they’re generated. If a payment processor that detects multiple transactions with the same code or codes being used to make transactions in the wrong order, it will disable the card. So a contactless card scammer can only use each stolen number for one transaction, and if the victim of a the scam uses the card again before the thief has time to make a fraudulent payment, all transactions on the card will be blocked.

    You should be more worried about waiters and cashiers then somebody in a crowd grabbing your data.

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    Your hair look like poop, Bob! - Wanker.
    1. Re:FUD by Dr_Barnowl · · Score: 4, Insightful

      Untrue ; waiters and cashiers will eventually get busted by data mining - you just need to correlate the transactions that pay for food and note the common location, then go through their time cards.

      Whereas with wireless, you could collect the data in a location not covered by security cams, and transmit it, encrypted (how ironic) to avoid detection, to another location where payments are processed. A crowded subway car would be ideal - people are not going to be using their cards, and it's the ultimate in cultured anonymity - everyone goes out of their way not to notice anyone else.

  4. The Obvious Solution* by nick357 · · Score: 5, Funny

    Put her in jail for teaching others how to defraud the public!!!!

    * Obvious to the credit card industry

  5. This is sort of old news. by MrCrassic · · Score: 4, Insightful

    Its been well known that RFID cards are suspectible to this kind of threat. The only reason why jammers and blocks havent been enforced as much is because there haven't been enough cases of this happening to justify wide-scale enforcement. I really like the convenience of contactless payment systems and hope jammers and guards become ubitquitous enough for banks to provide them along with these cards.

  6. Glossing over one problem... by Shoten · · Score: 5, Informative

    Randy Vanderhoof, executive director of the industry group the Smart Card Alliance, points out that despite previous research on the contactless attack, no real-world instances of the fraud have ever been reported. “We’ve got six years of history, a hundred million users of these cards, and we haven’t seen any documented cases of this kind of fraudulent transaction. The reason we think that’s the case is that it’s very difficult to monetize this as a criminal,” says Vanderhoof. “The premise that this is a new threat is absolutely false and isn’t supported by [Paget's] demonstration.”

    In fact, contactless cards do offer one security feature traditional cards don’t: Along with the card’s 16-digit number and expiration date, the cards are set to offer up a one-time CVV code with every scan. Those codes can only be used for one transaction, and have to used in the order they’re generated. If a payment processor that detects multiple transactions with the same code or codes being used to make transactions in the wrong order, it will disable the card. So a contactless card scammer can only use each stolen number for one transaction, and if the victim of a the scam uses the card again before the thief has time to make a fraudulent payment, all transactions on the card will be blocked.

    So unlike the traditional magnetic stripe kind of card...and these get skimmed as well, mind you...with this attack you MUST be the next person to use the card's credentials. If not, the attack fails. It's not quite as bad as they make it out to be here. Furthermore, the cries that people have thrown up that someone could scan an entire room full of people at once are totally off-base. You'd need to create an induction field strong enough to energize the furthest cards...which would kill the nearest ones...and the cards would all jabber at the same time, mixing their signals. The RFID spec for these cards has no provision for collision detection or avoidance.

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    1. Re:Glossing over one problem... by barc0001 · · Score: 4, Interesting

      "with this attack you MUST be the next person to use the card's credentials." "the cries that people have thrown up that someone could scan an entire room full of people at once are totally off-base"

      Because it's impossible to build a rig that fits in a briefcase or backpack that scans cards within a meter or two of the holder and automatically runs scripted transactions as soon as a card is detected in range, right?

      Just because it's not AS bad a picture as the doomsayers are painting as a worst-case scenario doesn't mean it isn't ripe for exploitation.

    2. Re:Glossing over one problem... by oneiros27 · · Score: 4, Insightful

      So we'd have to funnel people through a chokepoint to isolate them ... and it might not work if they had more than one RFID enabled card in their wallet? And then you have to use it quickly, like this was done (while still on stage), rather than waiting for the person to try to make a legit transaction.

      I'm guessing that someone standing near the entrance to a subway system could work within those restrictions well enough that even if they got less than 1% success rate per person entering could still turn a nice little "profit" during rush-hour.

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    3. Re:Glossing over one problem... by CimmerianX · · Score: 5, Insightful

      >> the cards are set to offer up a one-time CVV code with every scan

      Wait, I thought RFID only offered up static information. Does this infer that the cards have some sort of logic onboard to generate these 'one-time codes' and have create a new code on every scan that matches up with its processor? How does this effect an inadvertent scan, do the codes get all out of sync? Is there resync logic as well? How would this be handled throught payment processors and 3rd party clearing houses?

      Now, someone enlighten me on this if it's true. But this sounds to me like total bullcrap.

    4. Re:Glossing over one problem... by Big+Smirk · · Score: 5, Informative

      Both, wrong... you less so.

      The credit cards use an induction form of RFID. The wavelengths in question are very long - would require a big antenna to transmitt and an equally big antenna on the card to receive.... well the cards aren't big enough. So you see this spiral pattern (inductive loop) that is the antenna.
      YAGI won't do it. You need something more along the lines of the magnetic sensors as you leave a store (EAS - Electronic Article surveillance).

      Credit cards are 13.56 MHz RFID. That's a wavelength of ~75ft. Not going to hide that YAGI very well....

      Nope, inductive loops. That's why it only works over about a meter because the strengths of the magnetic fields.

      --
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  7. Re:Mitigating factors by vlm · · Score: 4, Insightful

    Put two of these cards next to eachother, and they won't read. Put them in an aluminium card case, and they won't read. Move more than about 5 cm away from the card and it won't read.

    Stand in line at the convenience store behind victim. Tada, you just got owned.

    There are numerous ways around this problem. It shouldn't stop people from using the technology.

    Its about as secure as tatooing your social security number on your forehead, then telling people its safe because you need a telephoto lens from over 100 feet, or you can just wear a skimask all the time.

    --
    "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
  8. Re:Mitigating factors by berashith · · Score: 5, Insightful

    The issue isnt being able to mitigate, the issue is that if the CC companies convince everyone that this isnt possible, then they have an easy path to never having to pay out against fraud. They can just refuse to believe this exists, and tell anyone who had their card info stolen that the cause was their behavior, and then never have to honor a dime of repayment. This is enough to let everyone know that theft can occur this way, and liability remains with the CC companies.

  9. Use a Faraday Cage wallet by Woil · · Score: 5, Interesting

    I've been using a Faraday Cage wallet and passport holder by DIFRwear: http://difrwear.com/ for several years now. I don't work for them, but with the very cheap wallet prices and sturdy construction I've been very pleased with the products. I can testify that they do work as I have an RFID key card and it won't activate the door if in the wallet.

  10. What's the point of these? by twotacocombo · · Score: 4, Interesting

    What exactly is the advantage to these RFID credit cards? All the readers I've seen still require you to get the card close to it to work. Has the world really grown so lazy that we can no longer be bothered to make a vertical swiping motion? I can see the benefit for payment-enabled cell phones or key fobs, but credit cards? Seems like a solution to a problem that didn't exist.

  11. Re:Is this news? by Joce640k · · Score: 5, Insightful

    Why is it "hyperbole" if somebody can drain hundreds of bank accounts wirelessly with a $50 device?

    To me that sounds more like "panic stations, block all cards now!!"

    Why anybody needs RFID credit cards is beyond me anyway. Is it sooooo hard to swipe a card through a reader?

    PS: Why would the CVV number be on the RFID chip? Surely that's the secret only you and the company are supposed to know?

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    No sig today...
  12. false by dutchwhizzman · · Score: 4, Interesting

    You can read RFID cards in peoples wallets at 30 ft with a transponder with higher send signal and a better antenna. The same applied for multiple cards. Some reading devices won't process if there is more than one card in it's reach, but that's a software decision. Devices purpose made to leech RFIDs do not play by the rules and legislation set out for "proper" RFID equipment.

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    I was promised a flying car. Where is my flying car?
  13. Re:Is this news? by Rary · · Score: 4, Informative

    They actually have to bump the device up against your wallet.

    Not according to TFA:

    In a demonstration just before her talk, Paget read a card in my wallet through my back pocket without touching me, successfully obtaining the card’s information.

    There are many situations where we get close enough to random strangers for someone to pull this off.

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    "You cannot simultaneously prevent and prepare for war." -- Albert Einstein

  14. Mythbusters lost episode by speedlaw · · Score: 4, Interesting

    Wasn't RFID the subject of the Mythbusters episode that was "squelched" by Visa ? Adam made a few comments and the issue was clamped down upon by all. The credit card companies (huge advertisers-when you get 29% interest you have lots of money) made it clear that RFID weaknesses were not a subject to be discussed in public to a lay audience.

  15. Re:Is this news? by hawguy · · Score: 5, Informative

    If you have an unusually thin wallet, that may work. But the attacker isn't going to get closer and closer to you until it works. That would be pretty silly, and rather conspicuous. They are going to bump up against you.

    In a crowded commuter train or bus an attacker can inconspicuously bump his RFID reader containing backpack against 100 people without arising suspicion while pusing his way from one end of the train to the other. On a less crowded train, he can put his reader under the seat in front of him (many transit agencies use thin fiberglass or plastic seats) and get it to within 1/4 inch of the seated passenger's back pocket wallet.

    I have an RFID access key I keep in my wallet. I think if I get it within 2 or three millimeters of the reader it will work. But I never do it that way. I just slap my wallet against the reader. Suggesting that a criminal would do it differently is just silly.

    My RFID card key works 3 or 4 centimeters from the reader. Like you I usually slap it against the reader, but I'm not worried about making the reader suspicious about why I'm touching it. I've seen people who keep the card in their wallet do a butt touch on the reader and the card works fine through their wallet and clothes. If RFID card keys are any indication, then it would be trivial for a thief to get close enough to read the card without actually touching you - after all, pickpockets are already able to slip a wallet from a pocket undetected, so I think they can manage to get a card reader a few cm from your wallet without touching you.

    I'm not sure how Credit Card RFID chips differ from the RFID chips used in passports, but Passport RFID readers with high gain antennas have been used to read a passport RFID chip from hundreds of feet away.

  16. Re:Is this news? by Culture20 · · Score: 4, Informative

    I have an RFID access key I keep in my wallet. I think if I get it within 2 or three millimeters of the reader it will work.

    Mine works from 3 inches away. At a regional office, there's a reader that is twice as large on the wall, and just walking near it with my wallet in my pocket opens the door. It's not the card that determines distance; it's the reader. So maybe the crooks don't buy the $50 reader, maybe they go for the $2000 reader that works from two feet away, and set up shop in a van parked next to a busy sidewalk.