Gee, can't find the article about seven (?) states discovering DHS trying to get into election systems, (wonder why) but here are some:
https://www.cnbc.com/2016/12/08/homeland-security-tied-to-attempted-hack-of-georgias-election-database-report.html
https://www.computerworld.com/article/3173032/cybercrime-hacking/indiana-joins-idaho-in-claiming-dhs-tried-to-hack-their-election-systems.html
Of course, it quickly became "Russians."