US wireless carrier T-Mobile is informing some customers that their personal information was compromised in a recent data breach.
After being alerted to unauthorized activity on its systems, the company discovered that a malicious actor had access to a “small number” of T-Mobile accounts between late February and March 2023.
The exposed information varies, but includes customer names, birth dates, contact information, T-Mobile account PINs, account numbers and phone numbers, number of lines, Social Security numbers, IDs, balance, and internal T-Mobile codes used to service customer accounts.
According to the wireless carrier, no personal financial account information or call records were compromised in the incident.
T-Mobile reset the impacted customers’ account PINs and recommends that they update the PINs, either by logging in to T-Mobile.com or by contacting the company’s customer support.
The firm told the Maine Attorney General’s Office that only 836 individuals were impacted by the data breach.
This data breach might have been only a small incident, but it is the second one that T-Mobile has disclosed this year. In January, the company announced that a threat actor abused an API to access the personal information of roughly 37 million postpaid and prepaid customers.
Over the past five years, the carrier has suffered at least one cyberattack per year, including the 2022 Lapsus$ hack, a 2021 breach impacting more than 54 million customers, a 2020 compromise of employee emails, a 2019 data breach impacting prepaid customers, and a 2018 attack impacting 2 million customers.
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