T-Mobile Partners With Cybersecurity Experts at Mandiant, KPMG After Hack

By Dave Sebastian

T-Mobile US Inc. has struck long-term partnerships with experts at cybersecurity firm Mandiant and consulting firm KPMG LLG after the hack of the wireless company's user database, Chief Executive Mike Sievert said.

The company has been working with Mandiant for its forensic investigation since the incident's start. T-Mobile will work with Mandiant to develop a longer-term plan to mitigate and stabilize cybersecurity risks across the business, Mr. Sievert said Friday.

KPMG's cybersecurity team will review T-Mobile's security policies and performance measurement, Mr. Sievert said.

The breach is the third major customer-data leak that T-Mobile has disclosed in the past two years. The Bellevue, Wash., company is the second-largest U.S. mobile carrier with roughly 90 million cellphones connecting to its networks.

"To say we are disappointed and frustrated that this happened is an understatement," Mr. Sievert said. He added that the company is confident that there isn't an ongoing risk to customer data from the hack.

The company has notified just about every current T-Mobile customer or primary account holder who had their data compromised, Mr. Sievert said. Among other measures, the company has offered two years of free identity protection services with McAfee's ID theft protection service to all those who might have been affected by the breach, he said.

The company is actively coordinating with law enforcement on a criminal investigation, Mr. Sievert said.

John Binns, a 21-year-old American who moved to Turkey a few years ago, told The Wall Street Journal he was behind the security breach. He said the company's lax security eased his path into a cache of records with personal details on more than 50 million people and counting.

Write to Dave Sebastian at [e-mail]

(END) Dow Jones Newswires

August 27, 2021 08:52 ET (12:52 GMT)

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