Uhhh, what? The Select Committee on Intelligence in the U.S. Senate [published][1] a nearly 1,000 page report on this. Volume 5 begins with these findings:
> The Committee found that the Russian government engaged in an aggressive, multi-faceted effort to influence, or attempt to influence, the outcome of the 2016 presidential election.
> The fifth and final volume focuses on the counterintelligence threat, outlining a wide range of Russian efforts to influence the Trump Campaign and the 2016 election.
I highly recommend you [read][2] this yourself, but including a few top-level items of the counter intelligence threats:
> Taken as a whole, [Paul] Manafort's high-level access and willingness to share information with individuals closely affiliated with the Russian intelligence services, particularly Kilimnik and associates of Oleg Deripaska, represented a grave counterintelligence threat.
> The Committee found that Russian President Vladimir Putin ordered the Russian effort to hack computer networks and accounts affiliated with the Democratic Party and leak information damaging to Hillary Clinton and her campaign for president. Moscow's intent was to harm the Clinton Campaign, tarnish an expected Clinton presidential administration, help the Trump Campaign after Trump became the presumptive Republican nominee, and undermine the U.S. democratic process.
[1]: https://www.pbs.org/newshour/politics/senate-panel-finds-rus...
[2]: https://www.intelligence.senate.gov/publications/report-sele...