Personal information—including Social Security numbers—from about 73 million AT&T customers was leaked on the dark web earlier this month, the company said Saturday, though the source of the data is still under investigation, as it’s not known whether the leak came from within the company or one of its vendors.
Preliminary analysis of the leak indicates the data set appears to be from 2019 or earlier, impacting about 7.6 million current and 65.4 million former account holders, AT&T said.
The data set “includes personal information such as Social Security numbers,” among other information, according to AT&T, which said the data was released on the dark web about two weeks ago.
AT&T said there is no evidence of unauthorized access to its systems and the leak has yet to have a “material impact” on the company’s operations.
The company reset millions of customer account passwords after the leak, Bloomberg reported.
AT&T will communicate “proactively” with those impacted by the leak and offer credit “where applicable,” according to the company.
AT&T customers experienced a widespread outage last month, as over 70,000 customers lost cell service across Texas, Florida, California and other states. National Security Council spokesperson John Kirby said the Department of Homeland Security and the FBI both assisted the company with investigating the outage, subsequently confirming there was no evidence of a cyberattack. AT&T offered affected customers a $5 credit, which the company said was the “average cost of a full day of service,” while an internal review of the incident pointed to an internal error.
Other communications firms have been impacted by data leaks over the last year. Verizon informed the Maine Attorney General’s Office last month that more than 63,000 employees had their personal information exposed in an internal data breach in September. An internal investigation determined a Verizon employee obtained a file containing employee personal information without authorization, including their names, addresses, dates of birth and Social Security numbers, among other information. T-Mobile reported to the Maine Attorney General’s Office last May that 836 customers were impacted by a data breach, though no personal financial information was accessed. That breach followed another breach reported months earlier, which impacted about 37 million customers.
AT&T Will Pay Customers $5 Credit After Massive Outage (Forbes)
