T-Mobile confident no ongoing risks to user data from recent hack

(Reuters) — T-Mobile US Inc. said Friday it was confident there were no continuing risks to user data from a breach disclosed earlier this month that affected more than 53 million current, former and prospective customers.

The third-largest U.S. wireless carrier last week said personal data of more than 40 million former and prospective customers was stolen along with data from 7.8 million existing customers.

In another update, which came days after the U.S. Federal Communications Commission opened a probe into the breach, T-mobile revealed that 5.3 million additional wireless subscribers and 667,000 more accounts of former customers were impacted, bringing the total to more than 53 million.

“We recognize that many are asking exactly what happened. While we are actively coordinating with law enforcement on a criminal investigation, we are unable to disclose too many details,” CEO Mike Sievert said in a blog post Friday.

The wireless carrier in a filing also said it had partnered with experts at cybersecurity company Mandiant and consulting firm KPMG following the hack.

John Binns, a 21-year-old hacker who stole data of T-Mobile customers, said the company's security was “awful,” the Wall Street Journal reported Thursday.