Posts Tagged: briansclub hack


29
Jul 20

Here’s Why Credit Card Fraud is Still a Thing

Most of the civilized world years ago shifted to requiring computer chips in payment cards that make it far more expensive and difficult for thieves to clone and use them for fraud. One notable exception is the United States, which is still lurching toward this goal. Here’s a look at the havoc that lag has wrought, as seen through the purchasing patterns at one of the underground’s biggest stolen card shops that was hacked last year.

In October 2019, someone hacked BriansClub, a popular stolen card bazaar that uses this author’s likeness and name in its marketing. Whoever compromised the shop siphoned data on millions of card accounts that were acquired over four years through various illicit means from legitimate, hacked businesses around the globe — but mostly from U.S. merchants. That database was leaked to KrebsOnSecurity, which in turn shared it with multiple sources that help fight payment card fraud.

An ad for BriansClub has been using my name and likeness for years to peddle millions of stolen credit cards.

Among the recipients was Damon McCoy, an associate professor at New York University’s Tandon School of Engineering [full disclosure: NYU has been a longtime advertiser on this blog]. McCoy’s work in probing the credit card systems used by some of the world’s biggest purveyors of junk email greatly enriched the data that informed my 2014 book Spam Nation, and I wanted to make sure he and his colleagues had a crack at the BriansClub data as well.

McCoy and fellow NYU researchers found BriansClub earned close to $104 million in gross revenue from 2015 to early 2019, and listed over 19 million unique card numbers for sale. Around 97% of the inventory was stolen magnetic stripe data, commonly used to produce counterfeit cards for in-person payments.

“What surprised me most was there are still a lot of people swiping their cards for transactions here,” McCoy said.

In 2015, the major credit card associations instituted new rules that made it riskier and potentially more expensive for U.S. merchants to continue allowing customers to swipe the stripe instead of dip the chip. Complicating this transition was the fact that many card-issuing U.S. banks took years to replace their customer card stocks with chip-enabled cards, and countless retailers dragged their feet in updating their payment terminals to accept chip-based cards.

Indeed, three years later the U.S. Federal Reserve estimated (PDF) that 43.3 percent of in-person card payments were still being processed by reading the magnetic stripe instead of the chip. This might not have been such a big deal if payment terminals at many of those merchants weren’t also compromised with malicious software that copied the data when customers swiped their cards.

Following the 2015 liability shift, more than 84 percent of the non-chip cards advertised by BriansClub were sold, versus just 35 percent of chip-based cards during the same time period.

“All cards without a chip were in much higher demand,” McCoy said.

Perhaps surprisingly, McCoy and his fellow NYU researchers found BriansClub customers purchased only 40% of its overall inventory. But what they did buy supports the notion that crooks generally gravitate toward cards issued by financial institutions that are perceived as having fewer or more lax protections against fraud.

Source: NYU.

While the top 10 largest card issuers in the United States accounted for nearly half of the accounts put up for sale at BriansClub, only 32 percent of those accounts were sold — and at a roughly half the median price of those issued by small- and medium-sized institutions.

In contrast, more than half of the stolen cards issued by small and medium-sized institutions were purchased from the fraud shop. This was true even though by the end of 2018, 91 percent of cards for sale from medium-sized institutions were chip-based, and 89 percent from smaller banks and credit unions. Nearly all cards issued by the top ten largest U.S. card issuers (98 percent) were chip-enabled by that time.

REGION LOCK

The researchers found BriansClub customers strongly preferred cards issued by financial institutions in specific regions of the United States, specifically Colorado, Nevada, and South Carolina.

“For whatever reason, those regions were perceived as having lower anti-fraud systems or those that were not as effective,” McCoy said.

Cards compromised from merchants in South Carolina were in especially high demand, with fraudsters willing to spend twice as much on those cards per capita than any other state — roughly $1 per resident.

That sales trend also was reflected in the support tickets filed by BriansClub customers, who frequently were informed that cards tied to the southeastern United States were less likely to be restricted for use outside of the region.

Image: NYU.

McCoy said the lack of region locking also made stolen cards issued by banks in China something of a hot commodity, even though these cards demanded much higher prices (often more than $100 per account): The NYU researchers found virtually all available Chinese cards were sold soon after they were put up for sale. Ditto for the relatively few corporate and business cards for sale.

A lack of region locks may also have caused card thieves to gravitate toward buying up as many cards as they could from USAA, a savings bank that caters to active and former military service members and their immediate families. More than 83 percent of the available USAA cards were sold between 2015 and 2019, the researchers found.

Although Visa cards made up more than half of accounts put up for sale (12.1 million), just 36 percent were sold. MasterCards were the second most-plentiful (3.72 million), and yet more than 54 percent of them sold.

American Express and Discover, which unlike Visa and MasterCard are so-called “closed loop” networks that do not rely on third-party financial institutions to issue cards and manage fraud on them, saw 28.8 percent and 33 percent of their stolen cards purchased, respectively. Continue reading →


15
Oct 19

“BriansClub” Hack Rescues 26M Stolen Cards

BriansClub,” one of the largest underground stores for buying stolen credit card data, has itself been hacked. The data stolen from BriansClub encompasses more than 26 million credit and debit card records taken from hacked online and brick-and-mortar retailers over the past four years, including almost eight million records uploaded to the shop in 2019 alone.

An ad for BriansClub has been using my name and likeness for years to peddle millions of stolen credit cards.

Last month, KrebsOnSecurity was contacted by a source who shared a plain text file containing what was claimed to be the full database of cards for sale both currently and historically through BriansClub[.]at, a thriving fraud bazaar named after this author. Imitating my site, likeness and namesake, BriansClub even dubiously claims a copyright with a reference at the bottom of each page: “© 2019 Crabs on Security.”

Multiple people who reviewed the database shared by my source confirmed that the same credit card records also could be found in a more redacted form simply by searching the BriansClub Web site with a valid, properly-funded account.

All of the card data stolen from BriansClub was shared with multiple sources who work closely with financial institutions to identify and monitor or reissue cards that show up for sale in the cybercrime underground.

The leaked data shows that in 2015, BriansClub added just 1.7 million card records for sale. But business would pick up in each of the years that followed: In 2016, BriansClub uploaded 2.89 million stolen cards; 2017 saw some 4.9 million cards added; 2018 brought in 9.2 million more.

Between January and August 2019 (when this database snapshot was apparently taken), BriansClub added roughly 7.6 million cards.

Most of what’s on offer at BriansClub are “dumps,” strings of ones and zeros that — when encoded onto anything with a magnetic stripe the size of a credit card — can be used by thieves to purchase electronics, gift cards and other high-priced items at big box stores.

As shown in the table below (taken from this story), many federal hacking prosecutions involving stolen credit cards will for sentencing purposes value each stolen card record at $500, which is intended to represent the average loss per compromised cardholder.

The black market value, impact to consumers and banks, and liability associated with different types of card fraud.

STOLEN BACK FAIR AND SQUARE

An extensive analysis of the database indicates BriansClub holds approximately $414 million worth of stolen credit cards for sale, based on the pricing tiers listed on the site. That’s according to an analysis by Flashpoint, a security intelligence firm based in New York City.

Allison Nixon, the company’s director of security research, said the data suggests that between 2015 and August 2019, BriansClub sold roughly 9.1 million stolen credit cards, earning the site $126 million in sales (all sales are transacted in bitcoin).

If we take just the 9.1 million cards that were confirmed sold through BriansClub, we’re talking about more than $4 billion in likely losses at the $500 average loss per card figure from the Justice Department.

Also, it seems likely the total number of stolen credit cards for sale on BriansClub and related sites vastly exceeds the number of criminals who will buy such data. Shame on them for not investing more in marketing!

There’s no easy way to tell how many of the 26 million or so cards for sale at BriansClub are still valid, but the closest approximation of that — how many unsold cards have expiration dates in the future — indicates more than 14 million of them could still be valid.

The archive also reveals the proprietor(s) of BriansClub frequently uploaded new batches of stolen cards — some just a few thousand records, and others tens of thousands.

That’s because like many other carding sites, BriansClub mostly resells cards stolen by other cybercriminals — known as resellers or affiliates — who earn a percentage from each sale. It’s not yet clear how that revenue is shared in this case, but perhaps this information will be revealed in further analysis of the purloined database. Continue reading →