Millions of AT&T Inc. users received bad news from the third-largest US retail wireless carrier this Easter holiday weekend: Their personal data has been leaked onto the dark web.

In a press release on Saturday, the telecommunications giant said it has "determined that AT&T data-specific fields were contained in a data set released on the dark web approximately two weeks ago" and contains "personal information such as social security numbers."

"It is not yet known whether the data … originated from AT&T or one of its vendors," the company said, adding, "Currently, AT&T does not have evidence of unauthorized access to its systems resulting in exfiltration of the data set."

The statement continued: "Based on our preliminary analysis, the data set appears to be from 2019 or earlier, impacting approximately 7.6 million current AT&T account holders and approximately 65.4 million former account holders."

According to Bloomberg data, AT&T is the third-largest US retail wireless carrier, behind Verizon Communications Inc. and T-Mobile US Inc. It's also the largest telecom company that has disclosed the theft of its customers' personal information.

In 2022, T-Mobile paid $350 million to settle a class-action lawsuit over leaked data from over 50 million customers. Then, in 2023, the cellphone carrier revealed another major breach of "basic customer information" on 37 million customers.