April 18, 2016
GRU hackers use their access to the DCCC to breach the DNC using credentials stolen from DCCC employee with authorization to access DNC network. By June 2016, they had access to 33 DNC computers.[i]
[i] U.S. v. Viktor Borisovich Netyksho, et al (1:18-cr-215, District of Columbia) https://www.justice.gov/file/1080281/download