AT&T data breach49.1M accounts compromised on 2021-08-20

In March 2024, tens of millions of records allegedly breached from AT&T were posted to a popular hacking forum. Dating back to August 2021, the data was originally posted for sale before later being freely released. At the time, AT&T maintained that there had not been a breach of their systems and that the data originated from elsewhere. 12 days later, AT&T acknowledged that data fields specific to them were in the breach and that it was not yet known whether the breach occurred at their end or that of a vendor. AT&T also proceeded to reset customer account passcodes, an indicator that there was sufficient belief passcodes had been compromised. The incident exposed names, email and physical addresses, dates of birth, phone numbers and US social security numbers.