T-Mobile Says Hack Revealed Personal Data of 37 Million Customers

BOSTON — US wireless carrier T-Mobile said Thursday that an unknown attacker infiltrated its network in late November and stole data on 37 million customers, including addresses, phone numbers and dates of birth.

T-Mobile’s filing with the U.S. Securities and Exchange Commission says the data breach was discovered on January 5. The company said the data that was stolen – based on its investigation – did not include passwords or PINs, a bank account or a credit card. information, social security numbers, or other government-issued identification.

“Our investigation is still ongoing, but at this point the malicious activity appears to have been completely contained,” T-Mobile said, with no evidence that an attacker was able to infiltrate the company’s network. It says the data was first available on or around November 25th.

T-Mobile said it notified law enforcement and federal agencies, which it did not name. He did not immediately respond to an email asking for comment.

The company has been hacked multiple times in recent years. In a statement, T-Mobile said it does not expect the latest disruption to have a material impact on its operations. But Moody’s Investors Service senior analyst Neil Mack said in a statement that the breach raises questions about management’s cyber management and could alienate customers and attract the attention of the Federal Communications Commission and other regulators.

“While these cybersecurity breaches may not be systemic, their frequency at T-Mobile is a worrying outlier compared to their telecom counterparts,” Mack said.

In July, T-Mobile agreed to pay $350 million to customers who filed a class-action lawsuit after the company revealed in August 2021 that personal data, including social security numbers and driver’s license information, had been stolen. Nearly 80 million US residents were affected.

He also said at the time that he would spend $150 million through 2023 to strengthen the security of his data and other technologies.

Prior to the August 2021 invasion, the company reported violations in January 2021, November 2019 and August 2018 when customer information was accessed.

T-Mobile, based in Bellevue, Washington, became one of the largest mobile carriers in the country in 2020 after purchasing rival Sprint. He revealed that he had over 102 million customers since the merger.