UScellular, the fourth-largest wireless carrier in the US, has disclosed a data breach after the company’s billing system was hacked in December 2021. The mobile carrier said in data breach notification letters sent to 405 impacted individuals that the attackers also ported some of the affected customers’ numbers using personal information stolen in the incident. The carrier also reset the impacted customers’ security questions, answers, and personal identification numbers linked to their accounts. This is the second data breach in 2021 after hackers were also able to gain access to the carrier’s CRM software in January 2021.”]