Bale's fierce effort from outside the box was beaten away by Kameni and the Cameroon 'keeper then had to make a brilliant save to deny Ronaldo from close range moments later after he was teed up by Bale.
Ronaldo had a golden opportunity to extend his 11-game scoring streak in La Liga when presented with the ball inside the area thanks to a defensive mix-up, but even he couldn't beat Kameni as the former Espanyol stopper dived to his right to turn the ball to safety.
That miss nearly proved costly as Casillas spilled Samu Castillejo's low effort and recovered just in time to prevent Santa Cruz forcing the ball home from close range.
The European champions finally doubled their advantage when Bale sprinted onto Ronaldo's headed flick-on and, on his less-favoured right foot, fired high past the prone Kameni.
Isco's return to La Rosaleda then ended early when he was shown a second yellow card but, from the resulting free-kick, Malaga's luck was out again as this time Juanpi struck the woodwork and Angeleri blasted the rebound over.
Casillas was finally beaten in stoppage time when Santa Cruz headed home Arthur Boka's cross, but there was barely time for the Andalusians to launch another attack as they slipped to a first home defeat of the season.
Elsewhere, Athletic Bilbao defeated Getafe 2-1 and Espanyol scored a 2-1 win over Levante.
-AAP
