According to an NBC report, unknown hackers managed to infiltrate the Pentagon's General Staff email systems, resulting in the systems being down for two weeks.

The Pentagon confirmed that the email was taken offline as part of investigations into the case.
“Our goal is to identify and mitigate cybersecurity risks across our networks,” said Pentagon spokeswoman Lt. Col. Valerie Henderson. “With these goals in mind, we have taken the Headquarters network offline and are continuing to investigate. Our top priority is to restore service as quickly as possible.”
"As part of our policy and for security reasons, we do not disclose further details regarding cyber incidents or attacks against our networks," he added.
NBC, citing anonymous sources, reports that it is not yet clear whether the attack involved the Russian government or whether it was carried out by private Russian hackers. However, the sources say that the network on which the attack was based is based on an automated system, which collects a huge amount of data in bulk.
According to officials, whose identities have not been disclosed, the invasion took place on July 25 and affected about 4,000 military and civilian personnel.
Officials say no classified information was compromised or compromised, but the Pentagon has taken the email system offline to take the necessary action.
