The hosts had previously only found the net eight times in 12 matches, and they appeared to be struggling in front of goal again when they missed several chances in a deadlocked first period.
However, El Arabi came good after the interval to net his first treble in European football and fire Granada to a victory that sees them climb to eighth in the Spanish table.
The Moroccan striker was wayward with his finishing in the opening 45 minutes, though, as he firstly struck wide on 22 minutes, before missing over the crossbar a short time later, after Dimitri Foulquier's cross had found him unmarked and in a great position.
He found his radar to notch twice before the hour mark, but his efforts were separated by Juanmi's reply for Malaga.
El-Arabi pounced to convert a 48th-minute rebound, after visiting goalkeeper Willy Caballero had saved Rico's initial shot, but substitute Juanmi bagged within seconds of his introduction to bring Malaga level.
The 20-year-old Spanish forward came off the bench to equalise for Bernd Schuster's side, tucking home from close range after the keeper, this time Granada's Roberto, could again only parry a preceding strike.
The home side's lead was restored five minutes later as El-Arabi was presented with another tap in, when he got on the end of a square pass from Yacine Brahimi, who had made a powerful run into the box.
El-Arabi completed his hat-trick on 78 minutes, when he slid the ball under the outrushing Caballero to secure his team a two-goal victory which sends them four points clear of their mid-table rivals.