Malmo, the lowest-ranked side in the Playoffs, had hit back to level the series from 2-0 down, but after a 3-2 win in Gavle in game five, Brynas sealed their place in the semis with the only away win of the series, 5-2.
The visitors were pressing for the opening goal in the first period, and the Malmo defence finally caved in the 16th minute, when Anton Rodin was given time in the attacking zone to set up Theo Lindstein, who found the top corner.
Linus Olund was sent through on goal in the second period and beat goaltender Oskar Blomgren to double the advantage, before Lassi Thomson hit back approaching the midpoint in the game on Malmo's first powerplay.
But hopes of a comeback slipped in the final minute of the second, when Oskar Lindblom squeezed the puck past Blomgren.
Robin Salo made it two from two on the powerplay for the Redhawks in the first minute of the third, but after conceding a penalty of their own, Lindblom made it 4-2 with just over 15 minutes left.
Malmo pulled their goaltender in a desperate attempt to keep their season alive, only to allow Greg Scott to score an empty-net goal and seal the win and a place in the last four for the newly-promoted club.
Farjestad have kept their 2024-25 season alive, winning the first of a possible three must-win matches 2-1 to reduce Skelleftea's lead in the series to 3-2.
Per Aslund got the go-ahead goal inside five minutes to settle the nerves inside the Löfbergs Arena with a tidy finish following Joel Kellman's pass.
But Skelleftea, on a three-match winning run, finally showed their good form midway through the game when Max Lindholm won possession back in the attacking zone and found the net unassisted.
After an interference call against Pontus Johansson, Kellman wrapped up a positive night for himself with a one-time finish on the powerplay for the Champions Hockey League runners-up.
The third period was end-to-end, but passed without incident, meaning Farjestad have taken the series to game six, which will be played tonight.
Frolunda are one win away from a place in the Semi-Finals after they ran out comfortable 6-2 winners over Timra in Gothenburg.
A flurry of activity in the final three minutes of the first period saw Frolunda go 2-1 ahead through Linus Weissbach and Noah Hasa either side of an Erik Walterholm goal for the visitors.
The Green and Reds maintained their scoring rate with two more goals in the second period from Jacob Peterson and Erik Thorell, before Timra kept themselves in the match with an Oliver Kapanen goal early in the third period.
But a powerplay goal from Mikael Ruohomaa killed the game as a contest, then an empty-netter from Isac Born was the icing on the cake for the home side.
Timra must now win game six at home tonight.