How do they know this if they never got the server and the only information they have is from CrowdStrike who is the only group that examined it?
Via Daily Caller:
Russian hackers retained access to the Democratic National Committee’s network until October 2016, despite private security firm CrowdStrike’s claim that it had expelled all intruders months earlier, according to an indictment filed Friday against 12 Russian intelligence operatives.
The indictment, filed by the office of Special Council Robert Mueller, reveals that CrowdStrike was unsuccessful in expelling intruders from the DNC’s networks in June and that a malicious program “remained on the DNC network until in or around October 2016.”
The hackers also gained access to DNC computers hosted on a third-party cloud-computing service around September 2016, which enabled them to steal data from the DNC by creating backups, or snapshots, of the DNC’s cloud-based systems.