> But on one occasion (...) Guccifer failed to activate the VPN client before logging on. As a result, he left a real, Moscow-based Internet Protocol address in

> But on one occasion (...) Guccifer failed to activate the VPN client before logging on. As a result, he left a real, Moscow-based Internet Protocol address in the server logs of an American social media company. (...) Working off the IP address, U.S. investigators identified Guccifer 2.0 as a particular GRU officer working out of the agency’s headquarters on Grizodubovoy Street in Moscow. https://www.thedailybeast.com/exclusive-lone-dnc-hacker-guccifer-20-slipped-up-and-revealed-he-was-a-russian-intelligence-officer https://www.thedailybeast.com/exclusive-lone-dnc-hacker-gucc... seems like intel community did plenty of their own investigations into this.