From the Document: "Foreign intelligence entities likely view U.S. elections as an opportunity to undermine confidence in our democratic institutions and processes, sow divisions in our society, weaken our alliances, and promote their political, economic, or ideological agendas. These entities operate in the seams of our democratic system to advance their interests, using the tools of traditional espionage in combination with cyber operations and influence campaigns. Foreign attempts to interfere with our elections fall into five distinct categories: 1) Cyber operations targeting election infrastructure, 2) Cyber operations targeting political parties, campaigns, and public officials, 3) Covert influence operations to assist or harm political organizations, campaigns, or public officials, 4) Covert influence operations to influence public opinion and sow division, 5) Covert efforts to influence policymakers and the public. This threat might take many forms, such as spreading disinformation, conducting hack-and-leak operations, or possibly manipulating data in a targeted fashion to influence the elections, and involves a wider range of foreign state and non-state actors than we have seen in the past, to include ideologically motivated entities and foreign cyber criminals. [...] Countering the complex and wide-ranging threats expected in these elections must be a core obligation of the entire USG [United States Government] and will require a whole-of-society approach, including support from the private sector and the active engagement of an informed public."
U.S Office of the Director of National Intelligence: https://www.dni.gov/