During the match on Tuesday, the German giants controlled the proceedings from the kick-off to grab a bright start thanks to the second-minute opener by Vidal, Xinhua news agency reported.
However, Bayern were unable to build up on their early goal as Benfica gained a foothold into the game.
Pep Guardiola's men seized the reins from the start to break deadlock with barley two minutes played after Juan Bernat's pinpoint cross found Vidal, who nodded home from inside the box, at the far post.
The hosts pressed the Portuguese outfit into the defence to work out a number of promising chances. Robert Lewandowski missed the target before Benfica custodian Ederson denied Douglas Costa's low effort with ten minutes on the clock.
"I am happy with the result because I know how good our opponents are. We head to Lisbon with the intention to advance into the next round," Bayern coach Pep Guardiola said. (IANS)