AT&T recently discovered that a data breach leaked personal information of millions of current and former customers online, exposing Social Security numbers and passcodes for over 73 million current and former customers. The stolen data is believed to have originated in 2019 or earlier and was found on the dark web and does not appear to include financial information or call history. As a precaution, AT&T has reset the passcodes of current customers and will offer credit monitoring services where needed. An investigation into the breach is ongoing. Similar large data breaches have affected AT&T in the past.