He hacked Sid Vicious and got his email string with Hillary.
From the indictment:
“From December 2012 to January 2014, Guccifer hacked into the email and social media accounts of high-profile victims, including a family member of two former U.S. presidents, a former U.S. Cabinet member, a former member of the U.S. Joint Chiefs of Staff and a former presidential advisor. After gaining unauthorized access to their email and social media accounts, Guccifer publicly released his victims’ private email correspondence, medical and financial information, and personal photographs. The indictment also alleges that in July and August 2013, Guccifer impersonated a victim after compromising the victim’s account.”