The Canadiens took a 2-1 lead on the power play at 5:51 of the first period when Nick Suzuki scored via a shot from the doorstep.
Suzuki doubled Montreal's lead with a shorthanded breakaway goal at 7:33 of the first period.
The Canadiens took a 4-1 lead when Jake Evans scored a wraparound goal at 16:36 of the second period.
Kirby Dach gave Montreal a 5-1 lead with a wraparound at 17:16 of the middle frame.
The Avs made it a 5-2 game at 18:06 of the middle frame when Kiviranta scored his second goal of the season via a shot from the left circle.