U.S. National Security Advisor Mike Waltz checks his mobile phone while attending a cabinet meeting held by U.S. President ...

The breach is considered a "major cybersecurity ... Read next BI Tech Memo An icon in the shape of an angle pointing down.

Chinese hackers have breached at least three major U.S. telecommunications providers in what appears to be an audacious espionage operation likely aimed in part at discovering the Chinese targets ...