The final at the Stade de France in Paris was delayed after police forcefully held back people trying to enter the ground. Liverpool lost the final 1-0 to Real Madrid.
Riot police sprayed tear gas at fans, including women and children. Liverpool fans, including the Liverpool city region mayor Steve Rotheram, also said they were robbed by criminals in the Paris suburb of Seine St Denis.
French Interior Minister Gerald Darmanin has consistently said that one of the main problems was large numbers of Liverpool fans turning up without valid tickets, but the Senate report highlighted other failings.
"Ticketing cannot be considered as the sole or main reason for the incidents," said Senator Laurent Lafon.
"There was a lack of organisation between the different parties concerned," added Lafon, pointing to insufficient co-ordination between police, security at the stadium and transport officials dealing with a public transport strike on the day.
Darmanin and French Sports Minister Amelie Oudea-Castera have apologised to supporters caught up in the trouble, but have maintained that many Liverpool supporters arrived with fake tickets -- something denied by Liverpool fans.
The spokesman for British Prime Minister Boris Johnson also said in May that Johnson was hugely disappointed by how Liverpool fans had been treated in Paris, while Darmanin had said Liverpool fans posed public order problems.
The trouble also marred France's image as a host of major sporting events, with the country due to stage the 2023 Rugby World Cup and 2024 Olympics.