The call records of some T-Mobile customers may have been viewed during a recent breach

T-Mobile suffered a security breach in December that could have exposed information and phone numbers related to calls for some of its customers. First reported by Bleeping computer, the information concerned by the violation do not include names on customer accounts, physical or email addresses, financial data, credit card information, social security numbers, tax IDs, passwords or PINs, the company said.

T-Mobile said in a statement emailed to The edge that it had notified “less than 0.2%” of its customers – which equates to around 200,000 people – that certain account information may have been accessed illegally. This information “may have included telephone numbers, the number of lines you have subscribed to, and in a small number of cases, certain call information collected as part of normal operation and service.” T-Mobile claims to have “identified this attack in early December and quickly put an end to the incident”. Affected customers have been informed by SMS.

In a notice posted on its website, T-Mobile said its security team “had put an end to malicious and unauthorized access” and launched an investigation to determine what information was involved. The company reported the situation to federal law enforcement.

T-Mobile has been the victim of several data breaches in recent years; in 2018, hackers accessed the personal information of approximately 2 million customers, including names, addresses and account numbers. In 2019, some of the company’s prepaid customers were affected by an access violation to names, addresses and account numbers. And in March 2020, a breach revealed the financial information of some T-Mobile customers, social security numbers and other account information.