T-Mobile, a wireless provider in the United States, reported earlier this week that an unidentified malicious intruder broke into its network in late November and stole information on 37 million customers, including addresses, phone numbers, and dates of birth.
The breach was found Jan. 5, according to T-Mobile, which disclosed this in a filing with the U.S. Securities and Exchange Commission. According to the company's investigation to date, the stolen data didn't include passwords or PINs, bank account or credit card information, Social Security numbers, or other official identifications.
The malicious activity "appears to be fully contained at this time, but our investigation is still ongoing," T-Mobile said, adding that the data was first accessed on or around Nov. 25.
In recent years, the company has experienced numerous hacks. In its filing, T-Mobile stated that it did not anticipate the most recent breach to materially affect its business.
However, Neil Mack, a senior analyst at Moody's Investors Service, stated in a statement that the breach raises concerns about management's cyber governance, may alienate customers, and may draw the attention of the Federal Communications Commission and other regulators.
The frequency of these cybersecurity incidents at T-Mobile is alarmingly high compared to that of its telecom competitors, Mack said, even though they may not be systemic in nature.
T-Mobile announced in August 2021 that personal information including Social Security numbers and driver's licence information had been stolen. As a result, the company agreed to pay $350 million to customers who brought a class action lawsuit. There were almost 80 million affected Americans.
Additionally, it announced at the time that it would invest $150 million in other technologies and data security through 2023.
Prior to the August 2021 intrusion, the company disclosed breaches in which customer information was accessed in January 2021, November 2019 and August 2018.
After acquiring rival Sprint in 2020, Bellevue, Washington-based T-Mobile rose to prominence as one of the nation's major providers of mobile services. After the merger, it claimed to have more than 102 million clients.