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Chip-and-Pin Vulnerable To Subtle Trickery

Zonk posted more than 7 years ago | from the i-feel-quite-safe dept.

Hardware Hacking 64

An anonymous reader writes "Cambridge University researchers, in an investigation for BBC Television's Watchdog programme, have demonstrated a man-in-the-middle attack for the chip-and-pin credit card security system used throughout the UK and Europe. In the attack, the card is inserted into a card-reader that has been tampered with, and the information transmitted in real-time to an accomplice who uses a specially modified card to make a higher-value purchase elsewhere. The modified card-reader shows only the expected amount, but the larger amount is deducted from the victim's bank account. It would not be easy to use this method in practice because the two transactions must be made simultaneously. The same team recently demonstrated a hacked chip-and-pin terminal playing Tetris."

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Other side of the pond (0)

Anonymous Coward | more than 7 years ago | (#17907772)

When do you think the U.S. congress will sell back the legislation protecting credit card holders to a $50 liability on fraudulent purchases? I mean, bankruptcy "reform" got through. It is not like they like us anymore (or, at least, last session).

The Tetris hack was a fake (1)

EmbeddedJanitor (597831) | more than 7 years ago | (#17907806)

It was not the real hardware hacked to play tetris. It was different hardware in the same box.

Sure, this shows that you can fool a user tothink they're using a valid machine, but it does not get at the transaction.

Re:The Tetris hack was a fake (4, Informative)

maubp (303462) | more than 7 years ago | (#17908098)

It was not the real hardware hacked to play tetris. It was different hardware in the same box.

Sure, this shows that you can fool a user to think they're using a valid machine, but it does not get at the transaction.
Have you read the article? There is a fake transaction at the victim's location which appears to be paying £20 for dinner. There is a real (but fraudulent) transaction at the jewelers at the same time for $2000 of diamonds.

The victim's card goes in the "fake pin machine" which is linked via laptops to a "fake card" in a "real pin machine" at another shop (in this case, a jewelers).

The laptop link makes it look like the victim's card is physically at the jewelers store, and takes care of all the validation. The victim is told the dinner price, and enters their PIN into the "fake PIN machine", which says "thank you" and prints a fake receipt. Meanwhile, the PIN number is then passed to the criminal at the jeweler to key into the real PIN machine and buy the diamonds.

Tricky to pull off due to the timing - but a real treat all the same.

Re:The Tetris hack was a fake (0)

Anonymous Coward | more than 7 years ago | (#17908282)

The bank will know that the unit has been screwed with but with the current system it's only the bank that will know. Card details and pin numbers can be recorded without the holder or merchant being warned. This means an attacker can copy cards *and* have the pin numbers to go out and have a little fun with.

Re:The Tetris hack was a fake (2, Interesting)

iangoldby (552781) | more than 7 years ago | (#17908908)

I wonder if you have misunderstood what is going on here.

The there is no connection between the bank and the card-reader that has been tampered with. As far as the bank is able to see, there has been a legitimate transaction for £2000. As far as the victim sees, the transaction is for only £20 (until he receives his statement one month later).

The point is: the actual transaction is £2000. The trickery is making the victim believe he is authorising a transaction of only £20 by presenting him with a fake terminal.

I believe also that this hack does not allow the card to be copied. My guess is that there is a one-time transaction code that the researchers cannot (yet) reproduce - remember this is a man-in-the-middle attack. That's why the victim's apparent authorisation of the £20 has to coincide with the real authorisation of the £2000.

Re:The Tetris hack was a fake (2, Insightful)

Tony Hoyle (11698) | more than 7 years ago | (#17911712)

Of course if you do £20 - £2000 then you get noticed real quick.

Do it at a petrol station or somewhere where the price varies a lot, add £1 onto the transaction (screening out the 'obvious' figures to avoid people who put exactly £20 of petrol in for example noticing the error), and have the 'real' transaction come from the 'real' retailer and you'd get away with it for quite a while.

Petrol station employees are paid minimum wage and not security checked & have an incentive to get involved in this too.

Don't stay in one place for too long, move around, and with a bit of luck and a following wind you'd be quite rich at the end of it.

Re:The Tetris hack was a fake (1)

ambrosen (176977) | more than 7 years ago | (#17911854)

No copying cards. These are cards with chips, so they're carrying functions, not just data.

Re:The Tetris hack was a fake (0)

Anonymous Coward | more than 7 years ago | (#17913666)

and pin numbers can be

"and PINs can be". (Since "PIN" stands for "personal identification number", you were in effect typing "and personal identification number numbers can be".)

Yes, BUT (1)

matr0x_x (919985) | more than 7 years ago | (#17907782)

This is still safer than traditional credit cards!

Re:Yes, BUT (1, Informative)

Anonymous Coward | more than 7 years ago | (#17908256)

This is still safer than traditional credit cards!
Not sure whether you're being sarcastic, but if not then safer for whom and in what way? Previously I had to sign for everything I bought on my card, and if it came to it then at least an expert should be able to spot a forgery in the event of a dispute. Now the only authorisation is typing in a 4 digit code in a crowded shop. Worse, a series of crowded shops time after time. If anyone managers to see my code then it just takes a pickpocket (or acquaintance) to get their hands on my card and they can enter into transactions indistinguishable from legitimate ones.

Re:Yes, BUT (2, Insightful)

mrcaseyj (902945) | more than 7 years ago | (#17909650)

AC wrote:

..if it came to it then at least an expert should be able to spot a forgery in the event of a dispute.
That won't do you any good because clerks can't distinguish from a legitimate signature and a forged one. Therefore if the owner of a card wants to cheat the bank, they can just sign their own signature with their left hand or something and then deny the charge. If the bank doesn't believe you when you say it was fraudulent then you'll be stuck with the charge (or the store will because they didn't check your ID). The fact that the signatures don't match does you no good.

Chip and pin is a massive improvement over the insane system we have in the US. It may have been sane back when computers were rare or expensive, but there's no excuse for it now. But chip and pin still has serious vulnerabilities, especially when used over the internet. Even with a card reader on your computer, the fact that operating systems like Windows and Linux will never be seriously secure, means that you can't trust what you see on the screen is what's going on over the wires. It's just a matter of time before the banks finally realize that the only solution is a device you carry with its own small display and keypad. Such a device would have a simple enough operating system and software that it might achieve a fairly strong level of security.

The other trend I see for the future is many more hackers learning to probe the dies of security chips. With the rapid increase in the number of devices relying on secret keys hidden in security chips, such as credit cards, motherboards, sattelite and cable tv, Blueray, and more, there will be greatly increasing demand for the ability to extract those keys. Electron microscopes or any other equipment to get into these chips can be bought, borrowed, or even built in one's garage. I'm sure that any chip can be defeated if the hacker has enough samples to work with. I don't know if the difficulty will make it impractical though.

This issue is not whether it is more secure... (1)

blorg (726186) | more than 7 years ago | (#17910016)

...The issue is that banks have used the argument that chip and pin is 100% secure to transfer liability for fraud away from themselves and onto the cardholder.

It is more secure than a signature that is never checked, sure, but 100% secure? No way.

This effort is designed to prove that it can theoretically be defeated without posession of the physical card, but you can easily imagine the decidely low-tech method of someone looking over your shoulder as you make a transaction and then pick-pocketing your card.

Why make it so hard? (0)

Anonymous Coward | more than 7 years ago | (#17907784)

Why not just add a $40+ fee over the normal $1-$5 fee they already charge at ATMs and call it a day.

attack easly detected (3, Interesting)

Technician (215283) | more than 7 years ago | (#17907878)

Someone with a close eye on their account will notice the missing money and pull up recent transactions online. Armed with reciepts and a printout of the impossible to make dual purchases with one card in two locations, the compromised machine can be shut down (de-authorised) and legal proceedings started. This attack has a name attached to the business using the terminal.

The attack is proof of concept, but it leaves too much of a trail.

Re:attack easly detected (1)

jimstapleton (999106) | more than 7 years ago | (#17907956)

wouldn't it be possible to use it with an online retailer somehow though?

It collects the information and simultaneiously
(A) Creates the online order with info from the card (or simply stores it for later use)
(B) Runs the designated order through another machine.

Re:attack easly detected (1)

maubp (303462) | more than 7 years ago | (#17908130)

wouldn't it be possible to use it with an online retailer somehow though?
There is no PIN check with an online payment - you wouldn't need the man in the middle. All you need for the fraudulent online payment is to steal the card details (ideally including the CV2 number printed on the signature strip). Plain old fashioned photography would be enough (both sides of the card).

Re:attack easly detected (0)

Anonymous Coward | more than 7 years ago | (#17908432)

dual purchases with one card in two locations

The purchase the cardholder thinks they're making isn't a real purchase in the system. Their machine might print off a receipt, but I can take an old calculator and make a receipt that's almost as convincing without even trying.

As for the trail, the cardholder would certainly know that they used their card at some place, and the manager there might even recall a technician coming by to service one of their terminals a week or two ago (any longer than that, and they might realize that the terminal isn't actually submitting charges to the bank anymore, assuming they actually reconcile their accounts and notice that money is missing... many small companies would just continue on autopilot without ever checking). If you're lucky, the store where the card was actually used might have a record of the apparent cardholder.

Re:attack easly detected (1)

profplump (309017) | more than 7 years ago | (#17908710)

If the terminal the customer thought they were using was not making charges, and that store's owner was not in on the plot, there's a good chance the owner would figure it out in short order -- he wouldn't be getting any money from sales that used that card terminal. And even if he was in on it he'd still be losing money for the items he's giving away without any payment. It seems unlikely that this plot could go undiscovered for very long.

Re:attack easly detected (1)

It'sYerMam (762418) | more than 7 years ago | (#17910522)

But it's going to be far easier to tamper with a terminal if the owner is in cahoots, so while you are correct, I don't think it really mitigates the problem.

Re:attack easly detected (1)

sndtech (738958) | more than 7 years ago | (#17909750)

The Machine that the unsuspecting customer uses (machine A) is not authorized and has no connection to any bank or financial institution, the only connection machine A has is to the laptop which is in the rucksack of the attacker at another location. the normal machine (machine B) accepts the wired card as a normal smart card, because it is simply relaying the data sent from machine A to machine B. how many people would keep a receipt for a low amount purchase? of course this whole idea depends on having the owner of machine A in on it, and having a friend who can complete the attack at Machine B.

Re:attack easly detected (1)

MbM (7065) | more than 7 years ago | (#17914994)

New hack -
Canceling out legitimate purchases with phony receipts showing simultaneous transactions.

'Watchdog' tonight (4, Insightful)

shrykk (747039) | more than 7 years ago | (#17907902)

This is due to be on 'Watchdog' (a popular consumers'-rights show) in about 45 minutes.

As I understand it, the point of this research is that the banks have been claiming that chip-and-pin terminals are completely tamper-proof. In fact, they may be tamper-proof from the banks' point of view (preventing fraudulent transactions by destroying encryption keys if the case is tampered with), they're not from the customers' point of view - a dodgy establishment or criminal employee could clone your card with a terminal that looks legit.

So, ripping out the innards and putting a machine playing Tetris inside looks silly, but demonstrates that the devices aren't inherently trustworthy. And this is the next step: showing that a card can be cloned and the details used to make a fraudulent transaction using modified hardware.

Re:'Watchdog' tonight (2, Insightful)

ds_job (896062) | more than 7 years ago | (#17908338)

The standard response from the Banks is:

"Our technology is infallible. You *must* have compromised your card / PIN. You will get no refund nor compensation."
What this does is point out that the first sentence is not correct and that the second does not automatically follow. I am not particularly protective of or abusive towards Chip-And-Pin but the "Nothing to do with me mate. You'll have to prove it." attitude of the banks is kind of annoying. I'm much more happy paying my taxes to find this kind of issue rather than modding the housing to play Tetris.

Re:'Watchdog' tonight (1)

chgros (690878) | more than 7 years ago | (#17908826)

a dodgy establishment or criminal employee could clone your card with a terminal that looks legit
Where did you get that from (for smart cards)? if this was the case they wouldn't have to do this complicated man-in-the-middle simultaneous transaction attack.

Re:'Watchdog' tonight (1)

Tony Hoyle (11698) | more than 7 years ago | (#17911342)

Oh come on... there is no standard 'look' for these things - they come in all shapes and sizes, and many larger shops still take the card off you and swipe on their terminal (so you don't even *see* the chip/pin thing they just hand you a keypad which is connected to the till & may or may not be encrypted or recording your pin for later use).

You really don't have to get hold of one of the legit boxes, just make something that looks passable and has an LCD display and card reader. That gets you the pin, assuming the data between the chip and the reader is encrypted. Getting the keys you'd need a proper box for.. this research proves these have weaknesses that allow you to get the data.

Re:'Watchdog' tonight (1)

shrykk (747039) | more than 7 years ago | (#17911714)

Where did you get that from (for smart cards)? if this was the case they wouldn't have to do this complicated man-in-the-middle simultaneous transaction attack.
You're right. As you say, it's not cloning, and what sjmurdoch and co demonstrated is a man-in-the-middle attack.

Your victim puts their card into a modified chip-and-pin terminal. At the same time, a criminal carrying a card connected to a hidden laptop goes to make a purchase in another store, putting the (fake) card in a (legitimate) terminal. The challenge-and-response between the legit terminal and the legit card are carried out remotely . The victim gets their $5 coffee for free but has just authorised payment for a high-value item elsewhere.

Anyway, yep - the crypto is good enough to stop cloning, but not this man-in-the-middle attack. However, this is unlikely to work well as a real scam - it's more of a proof-of-concept.

Is it a big deal? (1)

PCM2 (4486) | more than 7 years ago | (#17908946)

Here's what I don't get: It seems to me that, at least in most of the places I've been in Europe, European businesses are unwilling to turn away purchases from American tourists. Therefore, everyplace that uses the chip and PIN system can also accept American-style swipe-the-card transactions. So if your goal was merely to steal or clone a credit card and buy yourself a nice plate of frogs' legs, wouldn't it be easier to just do it American-style?

Second, do consumers not have credit card loss protection in Europe, the way they do in the U.S.? In the U.S., you're only liable for something like $50 on a fraudulent charge, and rarely do you end up paying even that. I had someone charge something like $950 to one of my cards recently, I spotted it right away, and it took something like a three-minute phone call to have the charge halted. They sent me a form in the mail, which I signed and returned, and that was the last I ever heard about it.

The real problem is not for the consumer and it's not for the credit card company. The problem is for the merchant. Here's how it works, at least in the U.S.: Someone steals my credit card. The thief walks into a Best Buy and purchases a TV. They walk out with the TV. I see the fraudulent charge on my bill. I call up my credit card company. They reverse the charge. Maybe someone investigates to see if they can find the person who made the charge. Let's say they're successful in their investigation (which actually happens more often than you think, mostly because most criminals are either stupid or greedy, or both). Unfortunately, however, the thief has already sold the TV and spent the money on crystal meth. Best Buy now has two options: A.) they can try to sue the thief to cover the cost of the TV; or B.) they can eat the loss and move on. Now let's say it isn't Best Buy. Let's say it's a single mom and pop store that's lost a TV and they have the same options. Sound fair to you?

That is the whole point of Chip+PIN (1)

blorg (726186) | more than 7 years ago | (#17910156)

do consumers not have credit card loss protection in Europe, the way they do in the U.S.? In the U.S., you're only liable for something like $50 on a fraudulent charge

Yes, we do. The whole point of Chip+PIN is to transfer the liability for fraud to the cardholder, as any transaction made using the PIN "must" have been made by that cardholder. So no fraud protection, no reversing the charge.

Re:'Watchdog' tonight (1, Insightful)

Anonymous Coward | more than 7 years ago | (#17910310)

The Watchdog piece was very misleading.

There's a demonstration of one thing (man-in-the-middle attack on Chip and PIN user) which is either very rare or non-existent in the wild (it's hard to be certain partly because banks are so secretive). That's Slashdot-worthy, but it shouldn't be a surprise to anyone who has used Chip and PIN and thought about it, and the real solution (every user owns their own tamper-resistant terminal) is too costly to consider in the near future.

To make this demo seem "relevant" to their show though, Watchdog wheels out a completely /different/ thing. A lot of people who definitely did not suffer this attack. Instead they are victims, supposedly, of "phantom withdrawal" in which the user can prove that they were elsewhere, but can't show that they had the card (iirc one of the women interviewed admits she'd lost it) nor that they properly protected their PIN. This "phantom withdrawal" has been a problem for banks for decades and is unrelated to Chip and PIN. There's often no way to tell the difference between trivial fraud by the customer and an accomplice, versus sophisticated fraud by a third party. Banks have taken the position that they do enough to prevent the latter already and courts have tended to agree.

Similarly, if you're found at home, asleep, covered in blood, with a knife clasped to your chest and the similarly bloody corpse of a teenage girl on your sofa, you'll be unlikely to satisfy a civil court that you were framed by an unidentified third party. You might cast enough doubt to keep yourself out of prison on a criminal charge, but the /balance/ of evidence is against you.

Hard to pull off with any card (1)

GiovanniZero (1006365) | more than 7 years ago | (#17907968)

I don't see any reason why this attack wouldn't work with a normal credit card machine (and not just the chip and pin cards). If you have hardware that has been tampered with the possibilities are endless really.

I personally wish that we did use the chip and pin cards in the US because it's better than signature. I usually sign for things with "PWNED" or I draw pictures of pacman or kung-fu stick figures and no one seems to notice. The security that comes with signatures is a joke.

Re:Hard to pull off with any card (1)

badfish99 (826052) | more than 7 years ago | (#17908384)

Actually, the security of signatures is in some ways better than chip-and-pin, from your point of view.

If someone steals your card and uses it, you simply repudiate the transactions. You can easily prove that they are not genuine, because the thief will not have been able to forge your signature.
If someone steals my chip-and-pin card and manages to use it, the bank will charge me for the transactions, and will simple laugh at me if I complain. Without a signature on the sales slip, I have got no proof that the transactions are fraudulent.

The security is certainly better for the bank: they can say "fraud has been reduced to zero". But this just means that the loss has been borne by me, not by them.

Re:Hard to pull off with any card (1)

Dreamstalker_wolf (823953) | more than 7 years ago | (#17910046)

When a CC of mine was stolen a few years ago, the thief did forge my signature (or try to). Probably did a fairly bad job of it too, but try as I might I couldn't get the merchant, delivery company or my bank to cough up the alleged signature so I could look at it. As far as they were concerned, someone signed my name (and used my card), the only person that could have done so must have been me. Nevermind that I wasn't even living at the delivery address at the time.

Re:Hard to pull off with any card (1)

Belial6 (794905) | more than 7 years ago | (#17913266)

This is largely why the 'Check Cards' are so bad for consumers. I don't understand why people don't get it. With a traditional credit card, if someone commits fraud on your account, you simply deny the charges, and you don't worry about it until it is proven that you made the charges. With the check cards (or as I call them 'give my money away for free cards') when you find a fraudulent charge, you have to go around to all of the businesses that you have written checks to that are now going to bounce because someone drained your checking account. It becomes a real problem when your mortgage, car payment, health insurance, homeowners insurance, and health insurance checks bounce. I don't want to hear from people that say you need to show ID, need a signiture, or have to have a pin. You don't need any of these to take your money at a gas stations, or any store with self checkout.

The worst part is that Visa advertises how easy it is commit fraud with these cards.

Re:Hard to pull off with any card (1)

Clazzy (958719) | more than 7 years ago | (#17908544)

Signatures are better theoretically but worse in practice as they require human verification whereas a machine does not care as long as a code is put in. Of course, humans are lazy and tend to accept the card regardless.
I'd say both have specific advantages and disadvantages, ultimately if the bank and customer wanted better security then both should be used side-by-side.

Check ID (1)

tinkerghost (944862) | more than 7 years ago | (#17909364)

I used to print "Check ID" on the signature space on the back of the card.
A clerk, had me sign the receipt, picked up the card - looked at the card & my signature, and then handed me back my card with a 'thank you'.

Re:Check ID (1)

Dreamstalker_wolf (823953) | more than 7 years ago | (#17910116)

IIRC, "Check ID" or "CID" written over your signature on the back of the card (with a green highlighter or similar so the sig is visible) is acceptable, but simply writing "See ID" (with no signature) is not. If a credit card does not have the holder's signature in the back panel, a business is within their rights to refuse the card (the card agreement states that a card is not valid for use until signed).

Re:Check ID (1)

Twanfox (185252) | more than 7 years ago | (#17910466)

I've had a sum total of one (1) company refuse me service because I wrote only 'See Photo ID' on the back of the card, instead of my signature. Oddly, it was some artist supply store. Everywhere else accepts it and, on larger purchases, will check the photo ID in order to validate. I even went so far in my grumblings to call the issuing company and ask whether the 'See Photo ID' "signature" was valid. The representative I talked to saw no reason why it would not, since the whole purpose of doing so was to prevent fraud. You'd think a merchant, the one most likely to get screwed, would be more than pleased for a card owner to attempt to prevent fraud instead of hanging on some trivial minutiae in order to piss off a customer and send the message that this merchant is not worth dealing with.

Here's the killer aspect of this all. While a signature may be easy to forge, a photo is less easy, requiring either noticeable alteration made to the card or a forged card to be made. Why do these cards NOT have a photo already on them? I've only ever heard of one company doing it.

Re:Hard to pull off with any card (0)

Anonymous Coward | more than 7 years ago | (#17909540)

Why don't they just introduce Credit Card Genuine Advantage - it doesn't allow the transaction even when it's perfectly legitimate!

Single bit check is not enough (1)

nickol (208154) | more than 7 years ago | (#17907970)

The method, proposed in the article is meaningless. If the timing
check is really 1-bit, the fake card can respond by itself, without
relaying any data. Is it on purpose ?

Much safer way is to measure time while performing a handshake.
Yes, there ARE some technical problems, but it would be a real check.

Re:Single bit check is not enough (1)

owlstead (636356) | more than 7 years ago | (#17908916)

"The extra step the researchers added is that the terminal sends the card a single bit *challenge* -- a 0 or 1 -- and the card *responds* in kind. The terminal can record how much time elapsed between sending and receiving the response, which would be a few nanoseconds in a normal transaction."

A challenge response is otherwise known as a handshake. They took a small challenge because otherwise the handshake would take too much time, making the method meaningless. A few nanoseconds is a bit on the possitive side, especially since the communication time between the reader and card would take much more than that.

Furthermore, it's impossible to use a signle bit. With 3DES you have a block size of 8 bytes, with AES the block size is 16 bytes and with RSA and other asymetric ciphers you normally use padding up to the key length (128 bytes for a 1024 bit key). So it's unclear to me what is exactly meant by this solution. Probably ZD messed up here; there are few people that really understand practical cryptography.

Re:Single bit check is not enough (1)

nickol (208154) | more than 7 years ago | (#17909640)

I see several possible scenarios :

FC = Fake Card, FT = Fake Terminal, C = Card, T=Terminal

1. Simplest

C: Hello, I'm card
T: Really ? Then we'll check how fast can you respond. Ping!
C: Pong!
T: 6ns, good time. Now let's shake hands...

Fake is obvious

2. More complicated
C: Hello, I'm card
T: Let's see. When I say, tell me your number, ready ? Ping!
C: 12345!
T: 20ns, looks like you're real !

Fake is also simple, the FT should first get the number from the card, then transmit it to FC.
Anyway, all needed information is stored on card, terminal is just asking it.

3. Improbable
C: Hello, I'm card
T: Let's see. I'll give you a number, you encrypt it and tell back. 12345!
C: Er.. well.. I need time to think...

4. More Secure

C: Hello, I'm card
T: Let's see. I'll give you a number, you tell it back to me at once. 12345!
C: 12345!
T: 20ns, and now we'll use this number as a base for the handshake. /* please note, there's not a SINGLE BIT transmitted from a terminal */

5. Really secure
C: Hello, I'm card
T: Good, and how fast can you do DES ?
C: 1000 clock cycles
T: Perfect. Let's synchronize clocks. 1-2-3-4! Now encrypt this number 12345.
C: (after EXACTLY 1000 clock cycles): 54321!
T: OK, let's go on. /* note that in this case it is impossible to use any Ethernet-like network - it cannot be synchronous */

Re:Single bit check is not enough (2, Informative)

sjmurdoch (193425) | more than 7 years ago | (#17909420)

Each exchange is one challenge bit and one response bit, so the timing is accurate, but this is repeated many times to give a high assurance that the real card is present (128 in the prototype). See the draft paper [] for the details.

Ultimate Financial Security (2, Funny)

ToneHog (234180) | more than 7 years ago | (#17907998)

For the truly security minded: a wallet, a handgun, and the bottom side of your mattress. No interest charges or minimum payments!

Re:Ultimate Financial Security (4, Funny)

sunwukong (412560) | more than 7 years ago | (#17908192)

"Lady, me and this gun here say that I'm going to pay cash for this and there's nothing you can do about it!"

"I'm sorry, sir, but I can't hear what you're saying through the mattress you're wearing."

Or did I misinterpret what you're suggesting?

Subtle? (1)

Timesprout (579035) | more than 7 years ago | (#17908026)

Its a fairly complicated attack, easily traced and could only probably only be executed once or twice per location before PC Plod comes calling due to the high visibility of the villians in pulling it off. Looks like way to little return for the effort and risk involved.

Coincidental Similarity? (1, Funny)

andy314159pi (787550) | more than 7 years ago | (#17908078)

Is there any relationship between Chip and Pin [] and Fish and Chips [] ?

nothing new here (2, Interesting)

mgb (30386) | more than 7 years ago | (#17908492)

So this along with the tetris hack basically says if you are a retailer and have access to a terminal or other means of getting hold of a persons credit or debit card then you can potentially do lots of dodgy stuff. Who knew!!!

Re:nothing new here (1)

IamTheRealMike (537420) | more than 7 years ago | (#17908982)

No, that's the whole point. If you have the card (stolen it) but not the PIN it is useless, regardless of what you do with a terminal. If you have a PIN (hacked terminal) but not the card, it's still useless. The simplest way to hack Chip'n'PIN for now is simply to bend the chip so it breaks, causing the terminals to fall back to magstripes.

Re:nothing new here (1)

celardore (844933) | more than 7 years ago | (#17909280)

You're right. Nothing new at all. And you don't even need to have a modified card reader. I was speaking to a guy in a small shop, I don't know how it came up, but he said that every card he puts through, they get a receipt with the full card number on it. That means that he can enter a "card not present" transaction later. It will show up on your statement, so it's traceable, but they could put these transactions through whenever they please. I guess chances are that this already happens a lot.
You need to keep a track of your bank statement, don't trust what your balance is until you have cross referenced it with your own records. Direct Debits, standing orders, cheques, ATM withdrawals - keep a note of all these on paper. Trust me, it will highlight any discrepancies.

Re:nothing new here (1)

Tony Hoyle (11698) | more than 7 years ago | (#17911522)

In the UK PC World still print your entire CC number *and* expiry date on receipts (or they did a couple of months ago... I complained... again... one day they'll listen).

A bit of dumpster diving around one of them and you'd have a handful of legit card numbers to clone. All you're missing is the CVE.

Now find online retailers that don't ask for the CVE (admittedly getting fewer... My ISP doesn't for example).

Or just pay for car parks, which aren't chip/pin enabled and just take the magstripe and debit your card.

What I learned at OfficeMax (1)

jmichaelg (148257) | more than 7 years ago | (#17908818)

When I saw that Officemax [] was stupidly storing atm pins, I gave up. Now, the only machine that sees my atm card is my bank's. And even there, I look at the machine to see that it hasn't been tampered with. []

For everyone else, I've reverted to checks and cash.

Classic Quote... (2, Funny)

ayjay29 (144994) | more than 7 years ago | (#17909118)

Anne Robbinson my arse!


I am watching a dog.

I don't get it (2, Interesting)

giminy (94188) | more than 7 years ago | (#17909400)

This is neat, but it's not exciting. I've written a smartcard proxy service that could also be used for evil. It works by capturing the client certificate request from a tls handshake, and sends the signed response to the server (some older web apps don't know how to use pkcs#11 libraries, which is what this is used strips the client cert request out of the handshake so the client is none the wiser). I could rewrite my proxy to sign all kinds of data with the smartcard once the user gives the proxy his/her PIN...I could logon to banking sites and transfer money to me, buy stuff, essentially anything that the computer could do, and not inform the user.

I think Bruce Schneier's paper [] said it best. Sure the card is trustworthy, but when you're using any kind of smartcard, the card isn't the trust boundary. The card plus the computer (or pinpad in this case) that you're using it on is your trusted device conglomerate.

I think the real demonstration of this attack is that pinpads have vulnerabilities. Even that isn't earth-shattering. So does everything else where physical access is granted.

Which isn't to say that it isn't newsworthy (people should definitely be careful where they stick their card), but it does feed into idea #4 on the six dumbest ideas in computer security [] .

Relay attacks and terminal security (1)

owlstead (636356) | more than 7 years ago | (#17909434)

This attack is a form of a relay attack. These kind of attacks can be really, really hard to avoid. Basically you need both sides to be authenticated and communicate in a secure fashion. Both sides also need to be secured ("tamper resistant" or, if possible "tamper proof"). And to top it off you must be sure that anything you sign is really correct, and that the human input (if any) isn't listened upon. Of course, you must use something to confirm the transaction as well.

Basically it comes down to the fact that this is almost impossible to accomplish. As shown, it's pretty easy to replace the terminal by a fake one. I can remember an attack where a complete ATM was even replaced by a fake one. It might be possible to see keypresses through emitted radio waves. There is some discussion about contactless credit cards that don't need PIN entry for small transactions; bad idea, it's possible to simply relay the signal from other terminals and have someone use many, many small transactions from someone elses card. If you cannot trust the screen, there is literally no way to see which transaction you are signing - this is for instance a problem with many banking sites, even if they do authenticate individual (agregated) transactions.

Of course there are levels of security. Chip security is better than magnetic stripe security because the contents of the chip (and especially the key) cannot be (easily) copied. You can use a secure channel - if anywhere possible with terminal authentication - to hide the PIN as well, and really sign the transaction. Also, there is no need to store the PIN or PIN hash at the bank (currently any bank-employee with access to the PIN hash database can calculate the PIN in mere nanoseconds). But, as shown, it does *not* prevent against fake terminals - there are terminals with secure memory that could do terminal authentication and are tamper proof, but these are rather expensive.

I'm sorry if this response become something of a mess. Please be so kind to blame it on the inherent difficulty of secure transactions :)

Easier hack? (1)

ocularsinister (774024) | more than 7 years ago | (#17909516)

I may be missing something here, but I've always thought that a much simpler hack exists - albeit you would need to steal the card too, but we are talking about criminals here.

1a) Create a fake terminal that looks and operates like a genuine terminal. All the terminal does is record the 4 digit PIN.


1b) Place a camera such that it films the terminal as the card owner types in their 4 digit PIN.

2) Steal the card

3) Use the card + pin

In short, the terminal verifies itself to the credit card company, but not to me, the card owner. I don't trust 'em.

Way too complex (1)

AdamInParadise (257888) | more than 7 years ago | (#17910060)

Gee, there are much simpler attacks. In several cases, crooks setted up fake "standalone" ATMs that simply captured the card and the PIN code. Since to the user it appears that the card was swallowed by a legitimate ATM, the user is not going to report at stolen right away. The effect can be reinforced by a properly dressed (read: a suit) impostor telling the customer that there is a problem with the ATM and that they will get their card back in the mail.

Then crooks simply have to collect a bunch of valid cards with matching PINs. In many countries, the customer is responsible for purchase made with the right PIN if the card is not reported as stolen in 24 or 48H, so it may cause significant losses.

Re:Way too complex (0)

Anonymous Coward | more than 7 years ago | (#17913356)

or you could simply read all of the information from the card and print it on the magnetic strip of a new card.
The customer would key their pin, get their card back due to some 'unable to perform transaction' error. You'd have an exact copy of their card, their pin and they wouldn't know.

Or you could do some honest work and earn your own money.

Re:Way too complex (1)

AdamInParadise (257888) | more than 7 years ago | (#17917286)

That's a possibility but it would not work in every case with "chipped" cards. For example, on EMV cards (i.e. pretty much "chipped" banking card out there), the magnetic stripe contains a field stating that this card is "chipped" and that the "chip" transaction should be tried first if the payment terminal has a smartcard reader.

So if you only make a copy of the magnetic stripe on a card without a chip or with an inactive chip, there is a very high chance that the terminal will decline the transaction. As far as I can remember it's a setting that the merchant can turn on and off (broadly speaking).

Now, it is actually possible to clone the chip of some EMV cards (i.e. cards that support only the Static Data Authentication protocol), so your attack remains valid in some cases.

Cut out the middle man (1)

goatpunch (668594) | more than 7 years ago | (#17910410)

Should put the keypad and display on the card itself, it'd look like one of those 'credit card' calculators.

Re:Cut out the middle man (1)

Tony Hoyle (11698) | more than 7 years ago | (#17911646)

That's pretty much the only way it would work.

Just have to work on the shops (mainly larger ones) that insist on taking the card off you and using their own proprietary chip/pin system. They'd probably do the same "oh, we don't use those things.. here type your pin into this keypad".

Don't shop as Tesco - you PIN is not safe (0)

Alain Williams (2972) | more than 7 years ago | (#17913506)

A couple of years ago Tesco (the largest UK supermarket chain) taped over the top of the chip & pin terminals in their stores & other outlets. They insisted that, instead, you give the till attendant the card that they plug into the side of the till and enter your PIN into the chip & pin terminal that is connected to the till by a thin black wire.

The first time that I came across (all night petrol store) this I refused on the grounds that my bank had told me to not use terminals that had been tampered with. The till attendant could not offer an explanation other that this was how they now did it. I asked him to explain how this was still secure to be met with a blank stare. I paid in cash and left.

They still do this in their stores. It is quite simple: I no longer shop in Tesco since I do not believe that my pin would be guaranteed secure if I did.

What sort of problems could there be:

  • PIN sent down the wire in plain.
  • PIN sent to the card encrypted, open to a classic Man In The Middle attack.

The wire from chip & pin terminal goes via the till - this is dangerous, see below.

Once my PIN is out ... it must be because I told it to someone -- that is what the banks will say -- so I am liable for bills against the card. OK: to be really useful they would need to steal my card, that probably isn't too difficult - thousands of people are mugged/burgled every day.

I don't trust tills -- I have worked with them, they are general purpose PCs (probably running MS Windows) and can be remotely programmed over a network -- I used to work in an environment where program updates were sent out to tills -- so why not hack one to sniff card data. A techie with money problems could skim the PIN numbers and no one would likely notice, correlate with the addresses in the loyalty card database and tell his burgular friends which houses to visit.

Or maybe a ''maintainance'' man arrives, supposedly from head office, and fiddles with the till for a bit ... the average low paid all night joe would just allow this to happen. ''maintanance'' man returns a day later and unloads the data extracted -- no one at head office is any the wiser.

It gives me the shivers.

Just don't shop at Tesco - if enough people don't - they will get the message.

wow... (1)

tommyhj (944468) | more than 7 years ago | (#17914588)

We've had chip and pin here in Denmark for a number of years now. Before that we had magnetic cards and pins, with a photo on the back of the card and a signature. The photo was paramount, because if the pin wasn't used in transactions with only a signature, the photo would ensure that the person using the card was the owner - simple enough and pretty effective. Then they went and removed the photo... They also added a chip and hailed it's superior security, but didn't remove the magnetic stripe, and still allowed for signature-only transactions... One can only wonder... Maybe the banks WANT people to loose money to criminals, so they have to lend money at insane interests? Just put the damn photo back on, so anyone can see when a criminal tries to use my card! And I'm still amazed that you use signature only transactions in USA to this date. We've only used that here in Denmark as a backup when there was no electricity, and we're phasing it out now. Hilarious that you also print the actual signature directly ON the card, for anyone to copy - HAH, that's like writing your PIN on your card (which, sadly, some people also do...).

Has already been done in Denmark (1)

threaded (89367) | more than 7 years ago | (#17918138)

Some shops had their terminals replaced with modified units that captured the required card info and pin numbers which was then used by the bad guys at some later point. Aided and abetted I might add by an upgrade to the terminals wherein the new terminals look like the old ones and the old ones were discarded in a rather sloppy manner.
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