Dec. 18 marked the fourth anniversary of this site breaking the news about a breach at Target involving some 40 million customer credit and debit cards. It has been fascinating in the years since that epic intrusion to see how organized cyber thieves have shifted from targeting big box retailers to hacking a broad swath of small to mid-sized merchants.
In many ways, not much has changed: The biggest underground shops that sell stolen cards still index most of their cards by ZIP code. Only, the ZIP code corresponds not to the legitimate cardholder’s billing address but to the address of the hacked store at which the card in question was physically swiped (the reason for this is that buyers of these cards tend to prefer cards used by people who live in their geographic area, as the subsequent fraudulent use of those cards tends to set off fewer alarm bells at the issuing bank).
Last week I was researching a story published here this week on how a steep increase in transaction fees associated with Bitcoin is causing many carding shops to recommend alternate virtual currencies like Litecoin. And I noticed that popular carding store Joker’s Stash had just posted a new batch of cards dubbed “Dynamittte,” which boasted some 7 million cards advertised as “100 percent” valid — meaning the cards were so fresh that even the major credit card issuers probably didn’t yet know which retail or restaurant breach caused this particular breach.
Translation: These stolen cards were far more likely to still be active and useable after fraudsters encode the account numbers onto fake plastic and use the counterfeits to go shopping in big box stores.
I pinged a couple of sources who track when huge new batches of stolen cards hit the market, and both said the test cards they’d purchased from the Joker’s Stash Dynamittte batch mapped back to customers who all had one thing in common: They’d all recently eaten at a Jason’s Deli location.
Jason’s Deli is a fast casual restaurant chain based in Beaumont, Texas, with approximately 266 locations in 28 states. Seeking additional evidence as to the source of the breach, I turned to the Jason’s Deli Web site and scraped the ZIP codes for their various stores across the country. Then I began comparing those ZIPs with the ZIPs tied to this new Dynamittte batch of cards at Joker’s Stash.
Checking my work were the folks at Mindwise.io, a threat intelligence startup in California that monitors Dark Web marketplaces and tries to extract useful information from them. Mindwise found a nearly 100 percent overlap between the ZIP codes on the “Blasttt-US” unit of the Dynamittte cards for sale and the ZIP codes for Jason’s Deli locations.
Reached for comment, Jason’s Deli released the following statement:
“On Friday, Dec. 22, 2017, our company was notified by payment processors – the organizations that manage the electronic connections between Jason’s Deli locations and payment card issuers – that MasterCard security personnel had informed it that a large quantity of payment card information had appeared for sale on the ‘dark web,’ and that an analysis of the data indicated that at least a portion of the data may have come from various Jason’s Deli locations.”
“Jason’s Deli’s management immediately activated our response plan, including engagement of a leading threat response team, involvement of other forensic experts, and cooperation with law enforcement. Among the questions that investigators are working to determine is whether in fact a breach took place, and if so, to determine its scope, the method employed, and whether there is any continuing breach or vulnerability.”
“The investigation is in its early stages and, as is typical in such situations, we expect it will take some time to determine exactly what happened. Jason’s Deli will provide as much information as possible as the inquiry progresses, bearing in mind that security and law enforcement considerations may limit the amount of detail we can provide.”