T-Mobile was among the targets of the Salt Typhoon cyberattack uncovered in October, the Wall Street Journal reported. Other potentially breached companies include AT&T, Lumen and Verizon. Salt Typhoon, a hacker group allegedly linked to the Chinese government, aimed to access "the cellphone communications of high-value intelligence targets," according to the report.

A T-Mobile spokesperson told the WSJ that the company will "continue to monitor this closely, working with industry peers and the relevant authorities." The telecom firm said its data has not been impacted "in any significant way" so far.