This article refers to something occurring in 2014 with State Department email credentials and somehow loosely connecting that with the 2016 DNC email leak.
Besides showing that email is not really that secure in the first place (and evidenced by Ms. Clinton's own maintenance of a personal email server), it doesn't show any evidence that Cozy Bear was behind the DNC leak.
Assange himself seemed to implicate Seth Rich, a DNC staffer who was shot twice in the back in a mysterious murder in July of 2016:
https://www.rollingstone.com/politics/politics-news/will-jul...