“Our cybersecurity team recently identified and shut down a malicious attack against our email vendor that led to unauthorized access to certain T-Mobile employee email accounts, some of which contained account information for T-Mobile customers and employees," the mobile carrier said in a recent note to customers.
Data that may have been exposed includes customer names and addresses, phone numbers, account numbers, rate plans and features, and billing information, according to T-Mobile.
The company previously revealed a data breach in November 2019.