Russian hackers attacked the US Defense Department’s unclassified email system around July 25, sources tell NBC News, forcing the Pentagon to shut the system down for two weeks. The “sophisticated cyber intrusion” affected 4,000 civilian and military personnel of the Joint Chiefs of Staff.
NBC’s sources said that the hack appeared to use an automated system that rapidly gathered information and then sent it out to thousands of internet accounts, with suspected Russian hackers coordinating the attack by using “encrypted accounts on social media.” The suspicion that the hack came from Russia was first reported by The Daily Beast.
The anonymous officials said it was unclear whether the attack was carried out by individuals or the Russian government.
According to US officials, Russians may have been behind other cyberattacks on government computers this year, including intrusions into systems used by the State Department, the White House, and the Internal Revenue Service (IRS).