Ronaldo was instrumental in each Madrid goal, starting with his feed to Higuain for the opener after half an hour before he slotted Mesut Oezil's pass into the empty net in the 45th.
Oezil was fouled inside the area to set up a 50th-minute penalty that Ronaldo blasted past goalkeeper Rodrigo Galatto for his league-leading sixth goal of the season.
Kris Stadsgaard pulled one back for Malaga in the 55th but Ronaldo slid a pass over to Higuain 10 minutes later for the striker to fire his fourth of the season past the outstretched Galatto.
Madrid's most convincing road win of the season bolstered it for its midweek Champions League match against AC Milan.
“We are playing very well, growing with each game and stringing victories together,” Madrid goalkeeper Iker Casillas said. “Now some serious matches are coming up and we have to continue to rise to the occasion.”
Meanwhile, Andres Iniesta and Carles Puyol led Barcelona's rally as it joined Valencia with 16 points, one behind Madrid.
David Villa suited up against his former club for the first time since his summer transfer, while Barcelona also counted on Xavi Hernandez after the midfielder recovered from tendinitis.
While Valencia 'keeper Cesar Sanchez frustrated Villa from his first opportunity in the 20th minute, the visitors enjoyed the better first-half chances and took advantage of Barcelona's vulnerable defense for a 38th-minute opener on the counterattack at the Camp Nou Stadium.
Jeremy Mathieu burst into space down the left side to find Pablo Hernandez in front of goal to push it past Valdes despite the Catalan 'keeper getting a hand to it.
Valdes kept Valencia from stretching its lead with a save to Hernandez's shot from the edge of the area in the 41st, while Mathieu blocked a Lionel Messi try at the other end just before the close of the half.
Iniesta started the fightback as the Barcelona midfielder swapped passes with Xavi before slotting a 47th-minute equalizer under Sanchez.
“That goal brought us back to life,” Iniesta said. “We changed some things in our system going into the second half so that it would work.” Xavi, who was returning from injury, orchestrated the 63rd-minute winner as Puyol sharply headed his centering cross past Sanchez into goal.
Barcelona would have run away with it if not for Sanchez thwarting Villa on three separate occasions, including a 1-on-1 situation in the 61st.
“To win these types of games will help us,” coach Pep Guardiola said. “In the first half it was impossible because we didn't have the ball.” At La Rosaleda Stadium, Madrid was unlucky not to be ahead earlier as Higuain's fierce shot came off the near post in the 19th while Sami Khedira rattled a long-range try off the crossbar in the 26th.
But Higuain made no mistake as he volleyed a shot back across goal under Galatto after being picked out by Ronaldo with a floated cross to the far post.
Malaga nearly answered as Quincy Owusu-Abeyie and Jose Salomon Rondon had chances before Oezil capped a Madrid recovery in the midfield by finding Ronaldo alone in front of goal to steer in the second.
“I have simply tried to work so that things go well for the team,” Ronaldo said. “I knew it was a matter of time before my goals came.” Edu Ramos dumped Oezil to the ground to set up Ronaldo's convincing penalty, but Stadsgaard shook off Khedira to tap a flicked-on corner into goal.
Higuain sealed it with a rising shot into the far corner as Madrid dominated the close, with Galatto making a number of impressive stops.
Earlier, Simao Sabrosa and Diego Costa scored in each half as Atletico Madrid beat neighbor Getafe 2-0.
Getafe enjoyed good pressure to start the match at Vicente Calderon Stadium but a foul on Atletico's Jose Antonio Reyes on the edge of the area set up the 37th-minute opener. Simao curled a free kick over the defensive wall and off the post, with the ball bouncing off the back of diving goalkeeper Jordi Codina into goal.
Atletico struggled to create chances without strikers Sergio Aguero and Diego Forlan in the starting lineup, although Forlan went on as a second-half substitute. But it was Juan Valera's quick dart along the right side that set up Diego Costa to sidefoot into the top of the net in the 73rd to seal the derby match between the Spanish capital clubs.
Atletico improved to 13 points, while Getafe stayed on 10.
In other seventh-round matches on Sunday, it's: Racing Santander vs. Almeria; Deportivo La Coruna vs. Osasuna; Levante vs. Real Sociedad; Mallorca vs. Espanyol; Athletic Bilbao vs. Zaragoza; and Sporting Gijon vs. Sevilla.
Hercules plays Villarreal, which has 15 points, on Monday.
