Credit cards are vulnerable to brute force kind attacks

https://metin.nextc.org/posts/Credit_Cards_Are_Vulnerable_To_Brute_Force_Kind_Attacks.html

by kodbraker • 3 months ago

241 192 3 months ago

metin.nextc.org

sixtyj• 3 months ago

People should have a separate card for online payments and have just enough money on it for a payment.

I know that I am naïve :)

Back to the article: Weak point was a password that lead to another merchant not using 3D secure.

It seems from the article that bad actors have fully automated system, so (big) merchants should have handle automatic login attempts from the same ip address with different accounts. I see it from our wordfence logs that ip rotation is not so quick so it could be handled with some permanent ip blocking.

kodbraker3• 3 months ago

I agree with the seperate card. That was my seperate card and luckily the amount was not quite big because of that.

Weak point was a password that lead to another merchant not using 3D secure

Well leaking a password shouldn't cause leaking a whole ass credit card data imo. The same data is printed on physical receipts the markets print, sometimes 4 digits, sometimes 10 digits. It's still possible to brute force from unattended physical receipts on the market.

mrbluecoat• 3 months ago

Not affiliated, but Capital One Eno virtual cards work well for this purpose.

kadoban2• 3 months ago

Tbh, fraud for credit cards is covered by the bank, so I typically just don't care. I just check my statements for anything that looks off.

stavros• 3 months ago

I think https://privacy.com is the best solution we can have with the current system.

Foofoobar12345• 3 months ago

Mercury now offers personal bank accounts. You can create virtual debit cards just like companies can with Brex/Mercury/Ramp etc.

psychoslave2• 3 months ago

My previous bank provided this virtual card service on demand. You create the card for a single purchase with a specific amount and that’s it. I moved to an other bank when getting an affordable mortgage loan became impossible in it for me.

lxgr20• 3 months ago

Why should they, if they're not liable for any resulting fraud of the status quo?

badgersnake2• 3 months ago

Oh okay, so this is why Amex launched the online card in the app that changes the Cvv2 every few minutes.

dogma1138• 3 months ago

Amex was late to the party with virtual cards.

majorchord• 3 months ago

None of my banks or credit cards support them... not sure how widespread it really is.

ranger_danger3• 3 months ago

I had no idea amex offers virtual cards... but I looked everywhere in the app and cannot find any such option?

kmoser• 3 months ago

https://www.americanexpress.com/en-gb/services/ways-to-pay/d...

fph• 3 months ago

3-digits? What is this, an OTP for ants?

badgersnake2• 3 months ago

Amex uses 4 but sure it ain’t a lot. Enough to stop this attach though.

janalsncm• 3 months ago

At least with a credit card you have some fraud protection. Report it and the charge should be reversed. And chargebacks are possible.

With a debit card you’re playing with your own money.

tptacek12• 3 months ago

That has not been my experience with debit cards in the US at major banks, at all, over decades.

(I'm pathologically avoidant of credit cards, which I think are mostly pointless.)

yladiz• 3 months ago

Why do you think they’re pointless?

lIl-IIIl• 3 months ago

You can reverse the charges on debit cards, but the money is withdrawn at the time the charge is made. This is not the case for credit cards.

epcoa3• 3 months ago

Well good for you. Us poors in the US like them for what they’re worth.

jabroni_salad2• 3 months ago

When my bank account got drained, I could not pay rent or any bills. I had enough cash for about a week of food. It took 4 weeks for the bank to decide I could be made whole. Ever since then I have never even put a debit card in my wallet. I know what the laws say. I have read endless "well banks usually[...]" type messages. and yet all the same I one day awoke to find myself transformed into a giant cockroach.

ranger_danger3• 3 months ago

In the US at least, there are still federal protections for debit card fraud: https://uslawexplained.com/debit_card

Natfan• 3 months ago

how is it not also your money when using a credit card? It's in the name, "credit" card. you have to pay it off, no? (i have never ever used a credit card)

idontwantthis• 3 months ago

It comes with fraud protection and your money does not move anywhere until the end of the next month. With a debit card your money moves immediately.

kadoban2• 3 months ago

As I understand it, debit cards do have some fraud protection too, but even if it's the same (I don't think it is), it's a way different power dynamic if you're begging for a bank to give you money back (debit card) vs just disputing your credit card bill.

In practice credit cards just have way better fraud protections.

skeeter20202• 3 months ago

You are making a purchase ON credit, and unless you are wildly negligent the merchant who accepts payment for the fraudulent purchase eats the costs. You may have to pay the balance owed while the chargeback works through the system but you will not ultimately pay for it.

Plus - like it or not - our society builds your credit based on your use of a credit card. And if you pay your balance in full every month I'm not sure why anyone would prefer paying up front (debit) vs. free financing.

bediger4000• 3 months ago

Some have speculated that the entire credit card system is compromised, end to end. I think the real question is why NSA didn't intervene in the early 1990s. Online commerce was just beginning, and the importance of electronic funds transfer was obvious, but the method wasn't set in stone. NSA knew about public key crypto well before the rest of us did. They could have helped set up very secure electronic payments, but chose not to for unknown reasons.

yieldcrv• 3 months ago

NSA prefers compromised security so that answers your question

Credit card system was already around for decades before though

fhdkweig• 3 months ago

I heard a rumor that NSA suggested changes to DES encryption that strengthened it from differential cryptanalysis attacks that the public cryptologists weren't aware of yet.

jongjong2• 3 months ago

Reminds me of when I wrote a lightweight blockchain from scratch including the Lamport OTS (quantum resistant) signature scheme and then most of the leaders from my crypto community at the time turned against me for no reason.

The signature scheme I implemented was thoroughly tested. Implemented from reading the Lamport and Merkel academic papers and under 1000 lines of code in total so pretty easy to audit... Nobody found an issue with it in 5 years. But the suppression was suspicious. The narrative of "Don't roll your own crypto" is suspicious... Is it really better to use the same library as hundreds of thousands of other projects? Is that really lower risk? Didn't we learn from the Axios hack that popularity doesn't provide security.

bagels• 3 months ago

"The RSA algorithm was publicly described in 1977 by Ron Rivest, Adi Shamir, and Leonard Adleman at MIT"

lxgr20• 3 months ago

What do you mean by "compromised end to end"? A compromise implies that something isn't working as originally designed.

Credit and debit cards (except for 3DS and EMV) are working exactly as designed; the design just isn't very good from a security perspective.

amluto• 3 months ago

Another mistake:

The data they took with the attempt of purchase is the card is still usable (not cancelled)

The payment flows should not distinguish between a nonexistent card, a cancelled card, and a valid card that needs 3D Secure. I bet the banks could even implement that without any cooperation on the part of the merchants.

gardenhedge• 3 months ago

Why not debit cards too?

J8K357R• 3 months ago

I once had a person that was hired by my company and then started bragging about finding a way to add stored value to gift cards. Then come to find out they were under investigation by the FBI. This was a government contractor mind you, so the biggest security guard I’ve ever seen showed up to escort them out.

kyleee• 3 months ago

What does “add stored value to gift cards” mean?

dboreham2• 3 months ago

I think it means "take a gift card with $10 value stored and make it a gift card with $20 stored".

Sohcahtoa823• 3 months ago

I'm guessing it means they can fraudulently add money to a store gift card without it costing anything.

janpeuker• 3 months ago

Payment processors don't allow just brute forcing all card numbers a.k.a. card enumeration or card testing [1][2] and card schemes penalise merchants and payment processors heavily if they don't take measures against it [3].

1) https://stripe.com/newsroom/news/card-testing-surge

2) https://stripe.com/blog/the-ml-flywheel-how-we-continually-i...

3) https://docs.stripe.com/disputes/monitoring-programs#enumera...

kodbraker3• 3 months ago

The rate they try becomes very non frequent when they use multiple card validation apis. I'm not sure how it can be related when it's different pan numbers, different source ips etc.

Enumerating CVC2 with a single PAN is a different story.

opengrass• 3 months ago

Until 6 years ago Stripe didn't obfuscate card numbers in API logs at all.

e28eta• 3 months ago

That’s untrue. While I would be willing to believe that for a brief period of time there was a bug that could expose it, having been at Stripe between 2017 and 2020, it was my experience that they had a robust system preventing PANs from being disclosed.

That included efforts to mask PANs that were in the wrong place.

We didn’t want them in our internal logging systems, and we certainly didn’t want to leak them back to the merchants.

julienchastang• 3 months ago

Related story and wondering if the OP may have been chasing red herrings. I recently noticed an unauthorized charge for a small amount on my credit card (something about FB/Meta). Likely someone probing the card to see if anyone would notice. I called the CC company, had them removed the charge, canceled the card and had them send me a new card (5-7 business days). With the brand new unused card (new CC number, new expiration date, new CVV), the fraudulent payments resumed (again FB/Meta). How is this possible? The reason: digital wallets. Your credit card number, etc. transfers via digital wallets even when you cancel the card. I again called the credit card company and this time, told them to cancel all the digital wallets (there were 99 of them!). There is no way to do this online. You have to speak to a human in a call center. You then have to sit through a lecture about how all your renewing payments are going to reset and you will have to re-establish them will all merchants. "Yes, I understand that. Please cancel the card and all digital wallets!" Then you have to hold for twenty minutes (why? what are they doing? manually canceling all the digital wallets?). The lesson I learned here is that canceling your credit card may not be what you think. Also recurring payments must be incredibly lucrative and canceling them must amount to a big loss in revenue. (Edited for grammar.)

kodbraker3• 3 months ago

For my case, it was almost certain. As it happened single day, the card i use was a virtual card only used in couple big ecommerce websites etc.

If it was leaked somewhere else, i think they wouldn't bother logging in some unrelated account of mine in an ecommerce website.

cj• 3 months ago

I’m not sure about “digital wallets”, but the concept of updating credit card details after a new card is issued does exist, and it’s a service offered by credit card companies.

Blog post from Stripe:

https://stripe.com/resources/more/what-is-a-card-account-upd...

SkiFire135• 3 months ago

There are also "network tokens" that allow you to skip this step and instead remain linked to the new credit card when it changes.

rconti• 3 months ago

Yep. I've been able to use the "wrong" (but still valid) expiration date on my AmEx for a long time. I've had other credit cards where the autopay info was never updated and it just kept working for at least 6 months.

resonantjacket52• 3 months ago

it's called automatic billing updaters.

Visa: Visa Account Updater (VAU) https://developer.visa.com/capabilities/vau Mastercard: Automatic Billing Updater (ABU)

it worked fine for sometime, but the problem is that now the stolen credentials are being refreshed now as well.

cft• 3 months ago

I also noticed that my Google Wallet cards no longer have expiration dates- when a card expires and they issue a new one, the Wallet card works without any intervention on my part

tety• 3 months ago

Digital wallets as in Apple/Google Pay? I had a similar thing happen and I am wondering what did you make of this double charge, what did the attackers do in your opinion?

resonantjacket52• 3 months ago

no it's like a continuation of your credit card for recurring payments.

It's called Automatic Billing Updater (ABU)

the idea is that if you ask for a new credit card after being stolen, your say utility providers or other like netflix subscriptions can seamlessly switch over to the new credit card number.

it worked fine for a while, but of course the problem is that afterwards the stolen credit card credentials started to be refreshed as well.

(used ai to fetch the list below).

Visa: Visa Account Updater (VAU) Mastercard: Automatic Billing Updater (ABU) American Express: Cardrefresher General: Recurring Payment Tokenization

thomk• 3 months ago

Check out privacy.com, you can make your own cards. One per service if you want.

at-fates-hands• 3 months ago

Been doing this for a while now for ebay and other stuff. I'm always shocked at how many people have no idea this exists.

thebruce87m• 3 months ago

Visited the site and the first thing it wanted me to do was accept optional cookies. Privacy.com wants to track me because of course it does.

pxeboot2• 3 months ago

I again called the credit card company and this time, told them to cancel all the digital wallets (there were 99 of them!). There is no way to do this online.

This is highly dependent on your bank. For example, Bank of America lets you view and delete any cards that have been added to a digital wallet right on their website.

lxgr20• 3 months ago

Only digital wallets, or also any merchant that saved the card using a token? The latter is getting more and more common, but usually happens transparently to the cardholder.

Theoretically, it would allow a pretty neat feature of being able to manage all merchants that have a copy of the card in the banking app and revoke said copies – but since token use is not mandatory, that would be fairly confusing, so I haven't seen this yet as far as I remember.

FWIW, India has taken a pretty radical step towards that future at a regulatory level by effectively mandating merchants to no longer store the underlying card number and use tokens instead. I suspect that such an interface would be more common there, but I don't have any personal experience.

Marsymars4• 3 months ago

Half of my cards can't even be added to non-iPhone devices without a verification phone call to some poor support agent who's never heard of a "Pixel Watch", has no idea what the workflow is on his end to manually verify cards being added, and just wants me to "use the iPhone app to verify".

Heaven forbid if I try to add a card to an Apple Wallet on a Mac where no iOS or Android app exists.

ph1lw• 3 months ago

Same here, had a 200 EUR charge from Meta / FB - still waiting for my new card.

8note• 3 months ago

if it was a 0 or 1 dollar auth, its likely a fraud check done by said company to make sure you still exist.

one or more of those digital wallets are some subscription supporting thing, and if that auth failed or had an address mismatch or wrong kind of card, they will disable your account until you update your card.

bmitch3020• 3 months ago

It's a shame that a disputed charge doesn't result in the credit card company reviewing how the charge was processed, invalidating only the single saved token with a single merchant. That would save everyone a lot of time and money.

bradley13• 3 months ago

Credit cards as a while use a security model from...what, the 1970s? Sure, they've patched by adding the 3-digit CVC, but really? A huge industry can't do better than that? Honestly, it's pathetic...

psychoslave2• 3 months ago

https://en.wikipedia.org/wiki/3-D_Secure

huggsboson• 3 months ago

BBVA has dynamic CVC

lxgr20• 3 months ago

Between 3DS for online payments and EMV for POS payments (both launched in the 1990s), payment cards could be plenty secure – if the industry were to decide to mandate them for every payment.

The fact that it hasn't is an interesting study in game theory and economics.

dataflow• 3 months ago

Okay but... so what? Authentication is a means, not an end. They seem to be missing that what matters at the end of the day is how much money/time/resources actually get lost, and who's on the hook for it. If that's negligible then isn't that mission accomplished? If we could live in a society where your name was enough and you didn't need a card number at all, and yet theft was still low and you still got your money back, that would be even better, not worse.

evan_a_a2• 3 months ago

As a consumer, I thought I was safe; when saving my credit card to a billion dollar valued european merchant, or when i purchase something from supermarket and ignore the receipt, but the reality is slightly different from that.
I got the money back via chargeback in short time.

So as evidenced, you are protected by the fraud infrastructure. The bank ate the loss for the fraud and you were made whole. In the end, the banking system cares about fraud loss. And they are exceptionally good at finding the fraud. Making changes to the card payment system is extremely difficult, due to the vast scale of the systems, so without a very good justification that a particular change will move the needle on fraud rates, the banks will opt to not make the changes.

mothballed4• 3 months ago

It's my experience that the bank will give up against a motivated chargeback counterparty.

My experience with ebay (stolen credit card) in particular was that things were going well until e-bay sent their stack of paperwork to my bank. Then my chargeback was reversed and shortly after that even my bank account was closed.

So you're not in the clear once you get your chargeback back. That is done initially while they give the other party time to respond. I think it took 30 days or so for ebay to bury me in paperwork, get the chargeback unwound again, and their schpeel was so effective that my bank themselves then accused me of being the fraudster.

As for

The bank ate the loss for the fraud

I'm not 100% that's true. The entire reason why the chargebackee wants to contest it is because either the chargebackee or the chargebacker is eating the loss. The bank isn't eating that loss. There is no way E-bay would have bothered contesting my chargeback and paying their white collar workers for professional time researching if the bank was just going to eat it.

NavinF3• 3 months ago

in what country?

spankalee• 3 months ago

The bank ate the loss for the fraud and you were made whole

_If_ you notice the fraudulent charge.

Sohcahtoa823• 3 months ago

It never ceases to amaze me how many people don't even look at their bank/credit card statements and just let their credit cards auto-pay.

Back when I was poor, I was logging into my bank and credit card accounts at least twice/week. I always knew within $20 how much money I had.

As a well-paid tech worker, I'm still checking at each paycheck (2x/month) and paying the credit card card off every time, but I'm still scanning the statements for any unexpected charges and to keep a pulse on my spending.

Fun anecdote, my wife started talking to me while I was scanning my statement once and she noticed there was a $20 charge from a business named "Your Side Chick" that she questioned in a joking way. It was from a food cart that specializes in chicken strips.

jonathanlydall4• 3 months ago

Banks don’t really eat the loss, instead they ensure all their services have enough of a markup to cover the cost of fraud.

All consumers collectively pay for all the fraud, it’s just that we don’t tend to realize it as it’s not a specific line item on any of our bills, instead we all pay just a little more than we should for everything we buy.

throawayonthe• 3 months ago

yes, obviously all of the bank's money comes from consumers. what other scenario do you see where a bank(etc) "eats the loss" but the money somehow comes from somewhere else

lxgr20• 3 months ago

The bank ate the loss for the fraud

Quite often, the merchant is unfortunately the one eating the fraud, which is creating a bit of a principal-agent problem (in that the issuing bank earns interchange on every transaction, so if they aren't liable for fraud, their default incentive would be to just approve as much as feasible and figure everything out later via chargebacks).

3DS changes that calculus quite a bit, though, and in-person payments are usually the issuing bank's liability as well.

mcoliver• 3 months ago

Virtual credit cards have been a thing for years. I remember bank of america or Citi providing them to me 15+ years ago. If I recall it was a java app or maybe even a standalone exe. Shocked they never took off more broadly.

Robinhood absolutely nails this. Best virtual credit card system I have ever used. So seamless. Can auth a card for one time use, 24 hours, or indefinite until you cancel. Such a great UI / UX

EvanAnderson• 3 months ago

MBNA (which got bought out by Chase) had a Flash-based virtual card app back in the early 2000's. I really enjoyed using it. I also can't understand why they haven't taken off, especially in the world of Everything Is A Subscription we're living in now. I adored being able to set expiration dates and spend limits to save ugly negotiations about ending subscriptions.

AnonEM00se• 3 months ago

It didn’t take off because it was easier to eat the costs of fraud than to maintain the system. It didn’t catch on simply because it’s pro-consumer.

chaqchase• 3 months ago

Rate limiting and anomaly detection are the real gatekeepers here. A lot of "fraud prevention" is still reactive.

jonathanlydall4• 3 months ago

If 3D secure was mandatory everywhere that would help a lot, but if I understand correctly, it’s not really used in the US and with them being so big, card issuers are largely forced to allow non 3D secure requests or their clients will be unable to use their cards for too many things.

So an enormously good anti-fraud mechanism is severely handicapped.

It’s really frustrating for most of the rest of the world.

I don’t get it, do US citizens prefer being defrauded over what is perceived as a slight inconvenience?

Even for non-victims of fraud, they still pay for the fraud as all merchants up the prices of their goods to cover fraud costs/insurance.

gnopgnip2• 3 months ago

How much is lost to fraud that would be prevented by 3d secure, 0.1%?

beejiu• 3 months ago

In Europe, the max interchange fee is 0.3%. In the US, the average is 2%. So the relative impact of fraud is much higher.

fckgw• 3 months ago

I don’t get it, do US citizens prefer being defrauded over what is perceived as a slight inconvenience?

Do you think we are requesting to have less secure payment methods or something?

No, we don't "prefer to get defrauded", but things like this are a matter of negotiation between the card issuers and the merchants.

Denvercoder95• 3 months ago

but things like this are a matter of negotiation between the card issuers and the merchants.

Not necessarily, the EU has mandated strong customer authentication by law (PSD2), and as a result has practically universal 3DSecure support.

eterm• 3 months ago

Legislate that the banks are liable for refunding this class of fraud and you'll find they suddenly take this stuff a lot more seriously and "discover" the technology.

mandevil• 3 months ago

No, the laws are different- and more consumer friendly in the US- so the US consumer behavior is different.

Back when credit cards were first starting out (which happened in the US) the US Congress passed a law- the Fair Credit Billing Act of 1974- that consumers were only liable for $50 of losses as long as they reported the missing credit card within 60 days of the end of the fraudulent billing cycle. This was back when credit cards purchases were all made on paper with the machine that went "kachunk" and transferred a carbon copy of your card- everything was done completely offline. That law has not been changed, in fact, most banks completely waive the $50 and don't hold card-holders liable for anything reported (basically, annoying a customer over $50 isn't worth it to the bank). Thanks to the internet, suddenly cards got a lot easier to steal and a lot easier to exploit- but banks are still on the hook for all losses reported within 60 days of the end of the cycle. The result is that American banks have invested an enormous amount in real-time monitoring of credit card transactions, and are doing lots of stuff to monitor this- they care deeply since ultimately they are on the hook- but the consumer doesn't care. This is why US card's from the consumer perspective are so much laxer, because our banks have invested far more on the back-end because the consumer is held harmless in a way they aren't with European cards.

As a totally separate issue, the EU has regulated the amount of interchange fees that card-companies can charge, but the US has not capped them. The result is that US card-holders can get significant kickbacks for using cards (especially true for the top decile of wealth), in a way that is functionally impossible with EU issued cards that have capped interchange fees. There is a big lawsuit happening now to try and allow merchants to only accept low-fee cards (the standard VISA/MC/AMEX deal requires treating all cards equally, which gives them an incentive to push people to higher interchange cards). We will see what happens with that suit, but until then, American high-spenders can have much higher rewards on their cards, which also encourages greater use of the cards- and making them have less friction than the EU versions.

X0Refraction• 3 months ago

Why would the law being different mean they wouldn't use 3DS though? Surely it'd cut out a good amount of fraud along with the realtime monitoring? I understand that US consumers don't have a stake in this, but can't all the banks just agree to enforce 3DS? I can't imagine Americans are going to stop using their cards because of a small amount of friction added

lxgr20• 3 months ago

This theory explains why cardholders in the US are still using cards despite these being relatively less secure than in other countries, but fails to explain why issuing banks wouldn't take steps to protect their own fraud losses, such as introducing 3DS or PINs.

The actual explanation lies in the game theory of fraud prevention; see my sibling comment for details.

SkiFire135• 3 months ago

Thanks to the internet, suddenly cards got a lot easier to steal and a lot easier to exploit- but banks are still on the hook for all losses reported within 60 days of the end of the cycle.

For card-not-present transactions (i.e. online ones) the liability is on the merchant. They however also have an incentive NOT to use 3DS because it adds real friction to purchases. I'm also not sure if all USA banks even support 3DS.

neom• 3 months ago

FWIW, HSBC USA Mastercard uses 3D secure if it's something you want and you're in the states.

lxgr20• 3 months ago

Capital One also offers it for their credit cards, which makes them the only ones usable in countries where requiring 3DS is common. (No idea why this is a thing actually – merchants get the fraud chargeback liability shift as soon as they request 3DS, whether the issuer actually supports it or not.)

The real problem is that in the US, almost no merchants request it in my experience, despite the fact that they'd get an almost free (in terms of conversion rate dropoff) liability shift. I suppose the few US issuers that do support it have a bad enough implementation that the conversion drop is still significant.

lxgr20• 3 months ago

I don’t get it, do US citizens prefer being defrauded over what is perceived as a slight inconvenience?

The general idea is that if the conversion rate drop of a given security mechanism is higher than the average fraud rate, it doesn't make financial sense to deploy it.

However, at the industry-wide level, this is a pretty classical coordination problem, in that conversion rate only drops because there still is a simpler alternative around unless all merchants and banks were to enforce 3DS at the same time. If there's nothing more convenient left to move to, users will for better or worse have to learn the new, more secure thing, and conversion rates will go up again.

This is what the EU has done with mandating 3DS for many payments, but even there regulators have recognized that a 100% coverage is counterproductive, and there's a sweet spot somewhere in the middle.

As more evidence for the same general idea: US credit cards don't have PINs, because any individual bank introducing them would see a huge drop in usage rates since customers would just use their competitor's card without a PIN instead. In other markets, all cards have PINs (whether due to regulatory invention or card network incentive), and people have just gotten used to them.

cnst• 3 months ago

IIRC, MasterCard SecureCode and Visa's verified-by-visa were more of a thing in the US maybe like decade or two ago? I think NewEgg and B&H did support it at one point? Afterwards, everyone has simply disabled the thing, and you simply get a wave-through by most issuers when shopping on foreign sites, where you get redirected to issuer's website, then back to the online shop, without having to type or confirm anything.

Back when it was a thing, it was quite a nightmare, where you had to register for a 3ds account, often separate from your normal online account, and keep a separate password etc. Then those iframe windows look exactly like the phishing websites, too.

Honestly, it's much ado about nothing. If the transaction is suspicious or likely fraudulent, today, you already get an SMS or an alert within bank's app on your phone. All you have to do is confirm and retry the transaction a minute later. This works for both in-person transactions, as well as remote ones, with the same flow, unlike 3ds, which only works for online shopping.

netik• 3 months ago

One other thing to add to the story is that the merchants can’t select what level of security they want from the credit card processor. For example, with authorize.net, you can accept the payment with the address doesn’t matter it doesn’t match.

I guess the real question here is how are they able to steal from you? Were they purchasing gift cards from a merchant with lax security?

It’s one thing to guess a number it’s another thing to get the money out of the system

Denvercoder95• 3 months ago

merchants can’t select what level of security they want from the credit card processor

That really depends on the processor; many processors do allow merchants specify your acceptance rules in quite deep detail.

There's a bit of a dichotomy in the processor market: on one side you have those that aim to make it simple for their customers and unburden them, while on the other side you have those that expose all the complexities and give intricate controls. The first side won't allow you to specify security requirements, while the second side will give you a hundred options (of course there's also processors positioning them in between). The two sides generally target different customers.

jwrallie• 3 months ago

Recently I got an sms from my bank about a suspicious transaction overseas from my wife’s card, it was literally listed as zero USD, at a time when she was not using her phone or computer.

I initially thought the sms itself was phishing, but after checking online, the sms format matched and the bank webpage ensured the feedback process will not ask for any information so we proceeded to confirm that we did not purchase anything.

The bank immediately cancelled the card and shipped a new one.

My initial thought is that the bank safety system could be overreacting, but it was likely that someone was doing exactly what is described in this article and the bank detected it earlier.

nout2• 3 months ago

I'll get the usual hate for this, but in this instance using bitcoin is safer, since it forces you to verify the transaction on your phone (i.e. you use your phone to pay - either scanning QR code or now NFC). In the US the Square payment terminals can now accept bitcoin from any lightning enabled wallet app, CashApp does it natively, etc.

tatersolid• 3 months ago

Bitcoin has no dispute/chargeback mechanism in case of error or fraud. That inherent unsafety trumps just about all other safety concerns for a practical payment network.

nout2• 2 months ago

In case of error you talk to the seller, if they are reasonable and care about their reputation, they pay you back (e.g. the Square seller devices have options for this). If they don't, you can try suing them. There's a wide group of people that are stealing from sellers (especially on Amazon and similar) by using the product and then returning it with made up issues. Bitcoin would help these businesses, since the settlement is final.

tialaramex• 3 months ago

This blog doesn't mention the most critical part

Settlement the part where the bank agrees to transfer money from your account (in this case increasing your debt on the card) to the merchant is completely separate from Authorization.

Authorization is the modern EMV ("Chip and pin") authentication, the CVV stuff for online, and any other mechanism by which the bank protects themselves from your fraud and, maybe, as an afterthought protects merchants.

The network is completely OK with Amazon saying here's a card number, we say they're paying us $400. That's just a settlement, goes on your bill. No sophisticated cryptography, nothing even as clever as a 4 digit PIN, or remembering your mother's maiden name, just OK, we trust you. Which means you, as a consumer, need to read your credit card bills and dispute anything you don't recognise or you'll pay.

There is very little incentive for the networks to care if you get ripped off. If you don't dispute it then everybody is happy, and if you do they just claw it back from the merchant and it's not their problem.

lxgr20• 3 months ago

if you do they just claw it back from the merchant and it's not their problem.

This is true for non-3DS online payments, but not for in-person payments or when using 3DS online. In those cases, the issuer is usually liable.

XorNot• 3 months ago

Why credit card numbers are full persistent baffles me. They were never meant to be memorable, and the whole process is electronic: surely this can be replaced by cryptography at this point?

I've deliberately demagnetized me and my wife's cards and we have black electrical tape over the numbers in public now.

Online purchases are the last remaining problem which would be completely solved if payments were to random keys rather then depending on everyone having the same number.

hocuspocus2• 3 months ago

PANs are indeed going away and every transaction could already be tokenized, today. But then the US were 20 years behind on EMV, and SCA is still not a thing.

jongjong2• 3 months ago

Credit cards are a horrible idea. We are essentially forced to use them. It's like giving every person you buy from the password to your bank account and trust them not to steal your money. Wire transfers are better.

lxgr20• 3 months ago

Arguably it's even more ironic how credit card applications work in the US: Based on yet another, even shorter number used as both an identifier and a bearer token, and that one you can't even change ever...

maxgashkov• 3 months ago

They absolutely are. Fun example: when Revolut launched in Japan few years back they had a period of a relatively explosive success (especially within the immigrant community), so most of the cards of the period were issued with the same expiration month and with the same IIN (I'm assuming specific to Japan as well) which left very little entropy and lead to brute-force attacks via merchants not requiring 3DS (Uber etc.). Within only one community (approx. 1.5k people) we have had a handful of a 100% verified cases when the card was compromised without any exposure at all (i.e. the card was not used online or offline).

In all cases Revolut promptly reverted the charges and eventually they did a complete reissue of the cards for Japanese market (not sure how they've got around the entropy issue: maybe they've randomized the expiry dates or spread out IINs some more).

edward1033• 3 months ago

Unlike US, in some regions such as JP,TW,HK, almost every online card transaction requires 3D Secure. But many real-world cases show that banks then refuse to take responsibility for fraudulent transactions once 3DS was completed, even when the OTP leak was caused by failures in the banking and telecom systems rather than by the cardholder.

hocuspocus2• 3 months ago

The EU has banned plain SMS tokens for SCA. You need an OTP + PIN or password, or more likely authorize the transaction from a mobile app with biometrics.

8cvor6j844qw_d6• 3 months ago

Pretty standard now to keep your card frozen when not in use, at least for me personally.

Some banks let you set specific limits for recurring payments.

fortran77• 3 months ago

We had a 5.15 cent charge for "TikTok" on a business card we never used. We have very good password hygene, and we have Ubikey authentication for all our business accounts. The bank initially told us to file a police report (!) for identity theft.

I knew it wasn't identity theft. We got a notice a week later that the charge had been reversed; we never bothered with a police report, we just cancelled the card. It had been flagged as suspicious by the bank when it was initially processed, but I'm not sure what was wrong. Perhaps one factor, like expiration date or zip code wasn't right.

I have a feeling it was stolen with some scheme like this where people just guess numbers by some algorithm.

exabrial• 3 months ago

It’s 2026, I have a laser guided vacuum robot that auto cleans my floors… we just flung people around the moon…

And we still don’t use public/private keys to secure transactions. Why

expedition32• 3 months ago

When I use my credit card I have to approve the transaction in my banking app. Which is pretty much unhackable. But that's too much friction for the average American because it gives you about 5 seconds to realise what you're doing lol.

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mcabert321• 3 months ago

Please just enter into your Google search and review this platform” and educate yourself before joining. Read BBC, Guardian, and Reddit articles/posts. Selfie camera doesn’t work, and they refuse to offer an alternative login method, so I can’t access my money. Keep getting same automated response(do some work you twits). They heavily spam my email, though. No customer service so imagine being stuck abroad with these absentee idiots as your lifeline, best learn to beg or busk in the local language. Am happy jeffsilbert 39 g mail com was my savior in getting my refund possible.

Credit cards are vulnerable to brute force kind attacks

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