
Picture: Shutterstock.
A cybersecurity agency says it has intercepted a big, distinctive stolen information set containing the names, addresses, e-mail addresses, telephone numbers, Social Safety Numbers and dates of start on almost 23 million Individuals. The agency’s evaluation of the info suggests it corresponds to present and former prospects of AT&T. The telecommunications big stopped wanting saying the info wasn’t theirs, nevertheless it maintains the information don’t seem to have come from its techniques and could also be tied to a earlier information incident at one other firm.
Milwaukee-based cybersecurity consultancy Maintain Safety mentioned it intercepted a 1.6 gigabyte compressed file on a well-liked darkish internet file-sharing web site. The biggest merchandise within the archive is a 3.6 gigabyte file referred to as “dbfull,” and it comprises 28.5 million information, together with 22.8 million distinctive e-mail addresses and 23 million distinctive SSNs. There aren’t any passwords within the database.
Maintain Safety founder Alex Holden mentioned plenty of patterns within the information counsel it pertains to AT&T prospects. For starters, e-mail addresses ending in “att.internet” accounted for 13.7 % of all addresses within the database, with addresses from SBCGLobal.internet and Bellsouth.internet — each AT&T firms — making up one other seven %. In distinction, Gmail customers made up greater than 30 % of the info set, with Yahoo addresses accounting for twenty-four %. Greater than 10,000 entries within the database checklist “none@att.com” within the e-mail area.

Maintain Safety discovered these e-mail domains account for 87% of all domains within the information set. Almost 21% belonged to AT&T prospects.
Holden’s crew additionally examined the variety of e-mail information that included an alias within the username portion of the e-mail, and located 293 e-mail addresses with plus addressing. Of these, 232 included an alias that indicated the client had signed up at some AT&T property; 190 of the aliased e-mail addresses had been “+att@”; 42 had been “+uverse@,” an oddly particular reference to an AT&T entity that included broadband Web. In September 2016, AT&T rebranded U-verse as AT&T Web.
In response to its web site, AT&T Web is obtainable in 21 states, together with Alabama, Arkansas, California, Florida, Georgia, Indiana, Kansas, Kentucky, Louisiana, Michigan, Missouri, Nevada, North Carolina, Ohio, Oklahoma, Tennessee, Texas and Wisconsin. Almost all the information within the database that include a state designation corresponded to these 21 states; all different states made up simply 1.64 % of the information, Maintain Safety discovered.

Picture: Maintain Safety.
The overwhelming majority of information on this database belong to shoppers, however virtually 13,000 of the entries are for company entities. Holden mentioned 387 of these company names began with “ATT,” with varied entries like “ATT PVT XLOW” showing 81 occasions. And many of the addresses for these entities are AT&T company workplaces.
How outdated is that this information? One clue could also be within the dates of start uncovered on this database. There are only a few information on this file with dates of start after 2000.
“Primarily based on these statistics, we see that the final important variety of subscribers born in March of 2000,” Holden advised KrebsOnSecurity, noting that AT&T requires new account holders to be 18 years of age or older. “Due to this fact, it is sensible that the dataset was seemingly created near March of 2018.”
There was additionally this anomaly: Holden mentioned one in all his analysts is an AT&T buyer with a 13-letter final identify, and that her AT&T invoice has all the time had the identical distinctive misspelling of her surname (they added yet one more letter). He mentioned the analyst’s identify is identically misspelled on this database.
KrebsOnSecurity shared the massive information set with AT&T, in addition to Maintain Safety’s evaluation of it. AT&T in the end declined to say whether or not all the folks within the database are or had been sooner or later AT&T prospects. The corporate mentioned the info seems to be a number of years outdated, and that “it’s not instantly attainable to find out the proportion which may be prospects.”
“This data doesn’t seem to have come from our techniques,” AT&T mentioned in a written assertion. “It could be tied to a earlier information incident at one other firm. It’s unlucky that information can proceed to floor over a number of years on the darkish internet. Nonetheless, prospects usually obtain notices after such incidents, and recommendation for ID theft is constant and might be discovered on-line.”
The corporate declined to elaborate on what they meant by “a earlier information incident at one other firm.”
However it appears seemingly that this database is expounded to 1 that went up on the market on a hacker discussion board on August 19, 2021. That public sale ran with the title “AT&T Database +70M (SSN/DOB),” and was supplied by ShinyHunters, a widely known risk actor with an extended historical past of compromising web sites and developer repositories to steal credentials or API keys.

Picture: BleepingComputer
ShinyHunters established the beginning value for the public sale at $200,000, however set the “flash” or “purchase it now” value at $1 million. The public sale additionally included a small sampling of the stolen data, however that pattern is not accessible. The hacker discussion board the place the ShinyHunters gross sales thread existed was seized by the FBI in April, and its alleged administrator arrested.
However cached copies of the public sale, as recorded by cyber intelligence agency Intel 471, present ShinyHunters obtained bids of as much as $230,000 for your complete database earlier than they suspended the sale.
“This thread has been deleted a number of occasions,” ShinyHunters wrote of their public sale dialogue on Sept. 6, 2021. “Due to this fact, the public sale is suspended. AT&T will probably be accessible on WHM as quickly as they settle for new distributors.”
The WHM initialism was a reference to the White Home Market, a darkish internet market that shut down in October 2021.
“In lots of circumstances, when a database is just not offered, ShinyHunters will launch it free of charge on hacker boards,” wrote BleepingComputer’s Lawrence Abrams, who broke the information of the public sale final 12 months and confronted AT&T in regards to the hackers’ claims.
AT&T gave Abrams the same assertion, saying the info didn’t come from their techniques.
“When requested whether or not the info could have come from a third-party associate, AT&T selected to not speculate,” Abrams wrote. “‘Given this data didn’t come from us, we are able to’t speculate on the place it got here from or whether or not it’s legitimate,’” AT&T advised BleepingComputer.
Requested to reply to AT&T’s denial, ShinyHunters advised BleepingComputer on the time, “I don’t care in the event that they don’t admit. I’m simply promoting.”
On June 1, 2022, a 21-year-old Frenchman was arrested in Morocco for allegedly being a member of ShinyHunters. Databreaches.internet experiences the defendant was arrested on an Interpol “Purple Discover” on the request of a U.S. federal prosecutor from Washington state.
Databreaches.internet suggests the warrant may very well be tied to a ShinyHunters theft in Might 2020, when the group introduced that they had exfiltrated 500 GB of Microsoft’s supply code from Microsoft’s personal GitHub repositories.
“Researchers assess that Shiny Hunters gained entry to roughly 1,200 personal repositories round March 28, 2020, which have since been secured,” reads a Might 2020 alert posted by the New Jersey Cybersecurity & Communications Integration Cell, a part throughout the New Jersey Workplace of Homeland Safety and Preparedness.
“Although the breach was largely dismissed as insignificant, some photographs of the listing itemizing seem to include supply code for Azure, Workplace, and a few Home windows runtimes, and issues have been raised concerning entry to personal API keys or passwords which will have been mistakenly included in some personal repositories,” the alert continues. “Moreover, Shiny Hunters is flooding darkish internet marketplaces with breached databases.”
Final month, T-Cellular agreed to pay $350 million to settle a consolidated class motion lawsuit over a breach in 2021 that affected 40 million present and former prospects. The breach got here to gentle on Aug. 16, 2021, when somebody beginning promoting tens of thousands and thousands of SSN/DOB information from T-Cellular on the identical hacker discussion board the place the ShinyHunters would submit their public sale for the claimed AT&T database simply three days later.
T-Cellular has not disclosed many particulars in regards to the “how” of final 12 months’s breach, nevertheless it mentioned the intruder(s) “leveraged their data of technical techniques, together with specialised instruments and capabilities, to realize entry to our testing environments after which used brute drive assaults and different strategies to make their means into different IT servers that included buyer information.”

A gross sales thread tied to the stolen T-Cellular buyer information.