WASHINGTON - Russian hackers seized control last year of the unclassified email system used by the US military's Joint Chiefs of Staff, CBS News reported on Thursday, citing an interview with then-Joint Chiefs of Staff Chairman Martin Dempsey.
Dempsey, who did not appear on camera, said he was alerted to the August 2015 attack by an early morning phone call from the director of the National Security Agency, Admiral Mike Rogers, according to CBS.
The email system is used by the Pentagon's Joint Staff, an organization of some 3,500 military officers and civilians who work for the chairman.
The hackers seized the passwords and electronic signatures used by Dempsey, an Army general who retired in September 2015, and hundreds of other senior officers to sign on to the network, according to CBS. The only way to stop the attack was to take the network down, CBS said.
The attack, which US officials now blame on Russia, was not spying, but a full-on assault whose only apparent purpose was to cause damage and force the Pentagon to replace both hardware and software, which took about two weeks to accomplish, according to CBS.