T-Mobile CEO Apologizes for Data Breach, Shares Info on Future Security Plans

T-Mobile CEO Mike Sievert today penned a letter to T-Mobile customers apologizing for the recent data breach that impacted more than 50 million current, former, and prospective T-Mobile users.

Data that included names, phone numbers, addresses, birth dates, social security numbers, driver's license and ID info, IMEI numbers, and IMSI numbers was stolen and has been offered for sale.

"We didn't live up to the expectations we have for ourselves to protect our customers," wrote Sievert. "Knowing that we failed to prevent this exposure is one of the hardest parts of this event. On behalf of everyone at Team Magenta, I want to say we are truly sorry."

He went on to say that T-Mobile is "disappointed and frustrated" and that keeping customer data safe is a responsibility that is taken "incredibly seriously." Preventing attacks is a "top priority" for the company.

The hacker who claims to have attacked T-Mobile's servers yesterday said that T-Mobile's security is "awful." The hacker said that he discovered an unprotected T-Mobile router in July and used that to access T-Mobile's data center in Washington, where he was able to get in using stored credentials.

Sievert said that T-Mobile is coordinating with law enforcement on a criminal investigation, and that the company is unable to disclose specific details at this time.

What we can share is that, in simplest terms, the bad actor leveraged their knowledge of technical systems, along with specialized tools and capabilities, to gain access to our testing environments and then used brute force attacks and other methods to make their way into other IT servers that included customer data.

T-Mobile has now notified every current T-Mobile customer about the data breach, and is working to notify former and prospective customers. Those affected can visit T-Mobile's website dedicated to the attack, which provides tools for signing up for free McAfee ID Theft Protection, setting up Scam Shield, and using the Account Takeover Protection service.

In an attempt to prevent future attacks, T-Mobile has entered long-term partnerships with cybersecurity experts at Mandiant and with consulting firm KPMG LLP. T-Mobile is planning a multi-year investment into beefing up its security.