T-Mobile said on Monday that hackers breached its internal servers and that company investigators are in the process of determining if the incident involves the theft of sensitive customer data.
“We have determined that unauthorized access to some T-Mobile data occurred, however we have not yet determined that there is any personal customer data involved,” the company said in a statement. “We have been working around the clock to investigate claims being made that T-Mobile data may have been illegally accessed.”
The statement came a day after Motherboard reported that a forum post was advertising a massive trove of data for sale. The post didn’t mention T-Mobile, but the seller told the publication that data related to more than 100 million people and that it came from T-Mobile servers.
The seller reportedly said that the data included social security numbers, phone numbers, names, physical addresses, unique IMEI numbers, and driver license numbers. Motherboard confirmed that samples of data made available by the seller “contained accurate information on T-Mobile customers.”