Posts Tagged: eBay

Nov 15

How Carders Can Use eBay as a Virtual ATM

How do fraudsters “cash out” stolen credit card data? Increasingly, they are selling in-demand but underpriced products on eBay that they don’t yet own. Once the auction is over, the auction fraudster uses stolen credit card data to buy the merchandise from an e-commerce store and have it shipped to the auction winner. Because the auction winners actually get what they bid on and unwittingly pay the fraudster, very often the only party left to dispute the charge is the legitimate cardholder.

So-called “triangulation fraud” — scammers using stolen cards to buy merchandise won at auction by other eBay members — is not a new scam. But it’s a crime that’s getting more sophisticated and automated, at least according to a victim retailer who reached out to KrebsOnSecurity recently after he was walloped in one such fraud scheme.

The victim company — which spoke on condition of anonymity — has a fairly strong e-commerce presence, and is growing rapidly. For the past two years, it was among the Top 500 online retailers as ranked by

The company was hit with over 40 orders across three weeks for products that later traced back to stolen credit card data. The victimized retailer said it was able to stop a few of the fraudulent transactions before the items shipped, but most of the sales were losses that the victim firm had to absorb.

Triangulation fraud. Image: eBay Enterprise.

Triangulation fraud. Image: eBay Enterprise.

The scheme works like this: An auction fraudster sets up one (or multiple) eBay accounts and sells legitimate products.  A customer buys the item from the seller (fraudster) on eBay and the money gets deposited in the fraudster’s PayPal account.

The fraudster then takes the eBay order information to another online retailer which sells the same item, buys the item using stolen credit card data, and has the item shipped to the address of the eBay customer that is expecting the item. The fraudster then walks away with the money.

One reason this scheme is so sneaky is that the eBay customers are happy because they got their product, so they never complain or question the company that sent them the product. For the retailer, the order looks normal: The customer contact info in the order form is partially accurate: It has the customer’s correct shipping address and name, but may list a phone number that goes somewhere else — perhaps to a voicemail owned and controlled by the fraudster.

“For the retailer who ships thousands of orders every day, this fraudulent activity really doesn’t raise any red flags,” my source — we’ll call him “Bill,” — told me. “The only way they eventually find out is with a sophisticated fraud screening program, or when the ‘chargeback’ from Visa or MasterCard finally comes to them from the owner of the stolen card.”

In an emailed statement, eBay said the use of stolen or fraudulent credit card numbers to purchase goods on eBay is by no means unique to eBay.

“We believe collaboration and cooperation is the best way to combat fraud and organized retail crime of this nature, working in partnership with retailers and law enforcement,” wrote Ryan Moore, eBay’s senior manager of global corporate affairs. Detecting this type of fraud, Moore said, “relies heavily on the tools that merchants use themselves, which includes understanding their customers and implementing the correct credit card authorization protocols.”

Moore declined to discuss the technology and approaches the eBay uses to fight triangulation fraud — saying eBay doesn’t want tip its hand to cybercriminals. But he said the company uses internal tools and risk models to identify suspicious activity on its platform, and that it trains hundreds of retailers and law enforcement on various types of fraud, including triangulation fraud.


Moore pointed to one education campaign on eBay’s site, which adds another wrinkle to this fraud scheme: Very often the people listing the item for sale on eBay are existing, long-time eBay members with good standing who get recruited to sell items via work-at-home job scams. These schemes typically advertise that the seller gets to keep a significant cut of the sale price — typically 30 percent.

A recruitment email from a work-at-home job scam that involves respondents in triangulation fraud. Source: eBay

A recruitment email from a work-at-home job scam that involves respondents in triangulation fraud. Source: eBay

Interesting, the guy selling carded goods stolen from Bill’s company has been on eBay for more than a decade and has a near-perfect customer feedback score. That seller is not being referenced in this story because his feedback page directly links to transactions from Bill’s company. Continue reading →

Aug 14

How Secure is Your Security Badge?

Security conferences are a great place to learn about the latest hacking tricks, tools and exploits, but they also remind us of important stuff that was shown to be hackable in previous years yet never really got fixed. Perhaps the best example of this at last week’s annual DefCon security conference in Las Vegas came from hackers who built on research first released in 2010 to show just how trivial it still is to read, modify and clone most HID cards — the rectangular white plastic “smart” cards that organizations worldwide distribute to employees for security badges.

HID iClass proximity card.

HID iClass proximity card.

Nearly four years ago, researchers at the Chaos Communication Congress (CCC), a security conference in Berlin, released a paper (PDF) demonstrating a serious vulnerability in smart cards made by Austin, Texas-based HID Global, by far the largest manufacturer of these devices. The CCC researchers showed that the card reader device that HID sells to validate the data stored on its then-new line of iClass proximity cards includes the master encryption key needed to read data on those cards.

More importantly, the researchers proved that anyone with physical access to one of these readers could extract the encryption key and use it to read, clone, and modify data stored on any HID cards made to work with those readers.

At the time, HID responded by modifying future models of card readers so that the firmware stored inside them could not be so easily dumped or read (i.e., the company removed the external serial interface on new readers). But according to researchers, HID never changed the master encryption key for its readers, likely because doing so would require customers using the product to modify or replace all of their readers and cards — a costly proposition by any measure given HID’s huge market share.

Unfortunately, this means that anyone with a modicum of hardware hacking skills, an eBay account, and a budget of less than $500 can grab a copy of the master encryption key and create a portable system for reading and cloning HID cards. At least, that was the gist of the DefCon talk given last week by the co-founders of Lares Consulting, a company that gets hired to test clients’ physical and network security.

Lares’ Joshua Perrymon and Eric Smith demonstrated how an HID parking garage reader capable of reading cards up to three feet away was purchased off of eBay and modified to fit inside of a common backpack. Wearing this backpack, an attacker looking to gain access to a building protected by HID’s iClass cards could obtain that access simply by walking up to a employee of the targeted organization and asking for directions, a light of a cigarette, or some other pretext.

Card cloning gear fits in a briefcase. Image: Lares Consulting.

Card cloning gear fits in a briefcase. Image: Lares Consulting.

Continue reading →

Sep 12

Researchers: Chip and PIN Enables ‘Chip and Skim’

Researchers in the United Kingdom say they’ve discovered mounting evidence that thieves have been quietly exploiting design flaws in a security system widely used in Europe to prevent credit and debit card fraud at cash machines and point-of-sale devices.

The innards of a chip-and-PIN enabled card.

At issue is an anti-fraud system called EMV (short for Europay, MasterCard and Visa), more commonly known as “chip-and-PIN.” Most European banks have EMV-enabled cards, which include a secret algorithm embedded in a chip that encodes the card data, making it more difficult for fraudsters to clone the cards for use at EMV-compliant terminals. Chip-and-PIN is not yet widely supported in the United States, but the major card brands are pushing banks and ATM makers to support the technology within the next two to three years.

EMV standards call for cards to be authenticated to a payment terminal or ATM by computing several bits of information, including the charge or withdrawal amount, the date, and a so-called “unpredictable number”. But researchers from the computer laboratory at Cambridge University say they discovered that some payment terminals and ATMs rely on little more than simple counters, or incrementing numbers that are quite predictable.

“The current problem is that instead of having the random number generated by the bank, it’s generated by the merchant terminal,” said Ross Anderson, professor of security engineering at Cambridge, and an author of a paper being released this week titled, “Chip and Skim: Cloning EMV cards with the Pre-Play Attack.”

Anderson said that the failure to specify that merchant terminals should insist on truly *random* numbers, instead of merely non-repeating numbers — is at the crux of the problem.

“This leads to two potential failures: If the merchant terminal doesn’t a generate random number, you’re stuffed,” he said in an interview. “And the second is if there is some wicked interception device between the merchant terminal and the bank, such as malware on the merchant’s server, then you’re also stuffed.”

The “pre-play” aspect of the attack mentioned in the title of their paper refers to the ability to predict the unpredictable number, which theoretically allows an attacker to record everything from the card transaction and to play it back and impersonate the card in additional transactions at a future date and location.

Anderson and a team of other researchers at Cambridge launched their research more than nine months ago, when they first began hearing from European bank card users who said they’d been victimized by fraud — even though they had not shared their PIN with anyone. The victims’ banks refused to reimburse the losses, arguing that the EMV technology made the claimed fraud impossible. But the researchers suspected that fraudsters had discovered a method of predicting the supposedly unpredictable number implementation used by specific point-of-sale devices or ATMs models.

Continue reading →

Mar 12

Banking on Badb in the Underweb

Underground Web sites can be a useful barometer for the daily volume of criminal trade in goods like stolen credit card numbers and hijacked PayPal or eBay accounts. And if the current low prices at one of Underweb’s newer and more brazen card shops are indicative of a trend, the market for these commodities has never been more cutthroat.

Visa, Amex cards for sale at is distinguishable from dozens of underground carding shops chiefly by its slick interface and tiny domain name, which borrows on the pseudonym and notoriety of the Underweb’s most recognizable carder. It’s difficult to say whether “Badb” himself would have endorsed the use of his brand for this particular venture, but it seems unlikely: The man alleged by U.S. authorities to be Badb — 29-year-old Vladislav Anatolievich Horohorin — has been in a French prison since his arrest there in 2010. Authorities believe Horohorin is one of the founding members of CarderPlanet, a site that helped move millions of stolen accounts. He remains jailed in France, fighting extradition to the United States (more about his case in an upcoming story).’s price list shows that purloined American Express and Discover accounts issued to Americans cost between $2.50 and $3 apiece, with MasterCard and Visa accounts commanding slightly lower prices ($2-$3). Cards of any type issued by banks in the United Kingdom or European Union fetch between $4-$7 each, while accounts from Canadian financial institutions cost between $3 to $5 a pop.

The site also sells verified PayPal and eBay accounts. Verified PayPal accounts with credit cards and bank accounts attached to them go for between 2-3$, while the same combination + access to the account holder’s email inbox increases the price by $2. PayPal accounts that are associated with bank and/or credit accounts and include a balance are sold for between 2 and 10 percent of the available balance. That rate is considerably lower than the last PayPal underground shop I reviewed, which charged 8 to 12 percent of the total compromised account balance.

Verified PayPal accounts with positive balances sell for between 2-10% of the available balance.

Ebay auction accounts are priced according to the number of positive “feedback” points that each victim account possesses (feedback is the core of eBay’s reputation system, whereby members evaluate their buying and selling experiences with other members). eBay accounts with fewer than 75 feedback history sell for $2 each, while those with higher levels of feedback command prices of $5 and higher apiece, because these accounts are more likely to be perceived as trustworthy by other eBay members.

But don’t count on paying for any of these goods with a credit card; accepts payment only through virtual currencies such as Liberty Reserve and WebMoney., like many other card shops, offers an a-la-carte, card-checking service that allows buyers to gauge the validity of stolen cards before or after purchasing them. Typically, these services will test stolen card numbers using a hijacked merchant account that initiates tiny charges or so-called pre-authorization checks against the card; if the charge or pre-auth clears, the card-checking service issues a “valid” response for the checked card number.

Continue reading →