T-Mobile confirms another data breach affecting 37 million customer accounts

T-Mobile, one of the largest wireless network operators in the United States, said on Thursday that it was investigating a data breach involving 37 million customer accounts.

In a disclosure notice filed to the U.S. Securities and Exchange Commission, the company explained the breach was discovered after it identified malicious activity on its networks on January 5.

A “bad actor was obtaining data through a single Application Programming Interface (‘API’) without authorization,” as the filing described the activity.

T-Mobile said …

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