AT&T Says Leaked Data of 70 Million People Is Not From Its Systems

An anonymous reader quotes a report from BleepingComputer: AT&T says a massive trove of data impacting 71 million people did not originate from its systems after a hacker leaked it on a cybercrime forum and claimed it was stolen in a 2021 breach of the company. While BleepingComputer has not been able to confirm the legitimacy of all the data in the database, we have confirmed some of the entries are accurate, including those whose data is not publicly accessible for scraping. The data is from an alleged 2021 AT&T data breach that a threat actor known as ShinyHunters attempted to sell on the RaidForums data theft forum for a starting price of $200,000 and incremental offers of $30,000. The hacker stated they would sell it immediately for $1 million.

AT&T told BleepingComputer then that the data did not originate from them and that its systems were not breached. 'Based on our investigation today, the information that appeared in an internet chat room does not appear to have come from our systems,' AT&T told BleepingComputer in 2021. When we told ShinyHunters that AT&T said the data did not originate from them, they replied, 'I don't care if they don't admit. I'm just selling.' AT&T continues to tell BleepingComputer today that they still see no evidence of a breach in their systems and still believe that this data did not originate from them.

Today, another threat actor known as MajorNelson leaked data from this alleged 2021 data breach for free on a hacking forum, claiming it was the data ShinyHunters attempted to sell in 2021. This data includes names, addresses, mobile phone numbers, encrypted date of birth, encrypted social security numbers, and other internal information. However, the threat actors have decrypted the birth dates and social security numbers and added them to another file in the leak, making those also accessible. BleepingComputer has reviewed the data, and while we cannot confirm that all 73 million lines are accurate, we verified some of the data contains correct information, including social security numbers, addresses, dates of birth, and phone numbers. Furthermore, other cybersecurity researchers, such as Dark Web Informer, who first told BleepingComputer about the leaked data, and VX-Underground have also confirmed some of the data to be accurate. Despite AT&T's statement, BleepingComputer says if you were an AT&T customer before and through 2021, it's '[safe] to assume that your data was exposed and can be used in targeted attacks.'

Have I Been Pwned's Troy Hunt writes: 'I have proven, with sufficient confidence, that the data is real and the impact is significant.'

Read more of this story at Slashdot.