T-Mobile has severed its connection to the unnamed wireline provider, which it suspects may still be compromised.

This morning, a report from Bloomberg states that T-Mobile engineers spotted suspicious behavior on the carrier's network devices that tipped off the carrier that it was under attack. Jeff Simon, T-Mobile 's chief security officer,

T-Mobile says the Chinese "Salt Typhoon" hackers who recently compromised its systems as part of a series of telecom breaches first hacked into some of its routers to explore ways to navigate laterally through the network.

Salt Typhoon deployed various methods to break into telecommunications firms that went far beyond a singular run-of-the-mill credential-stealing attempt, according to a person familiar.

A recent confirmed T-Mobile hack has been attributed to Salt Typhoon, the Chinese cyber espionage team that also breached Verizon and AT&T earlier in the year. That means the hackers were able to penetrate all three of the country's major mobile carriers in 2024.

Senator Mark Warner says booting 'Salt Typhoon' hackers could require physically replacing telecommunications equipment.