Stenson posted four birdies in a 4-under 68 to join Cabrera-Bello who birdied four of his closing five holes in a 7-under 65. Both players have an overall 14-under 202 on the Earth Course at Jumeirah Golf Estates.
McIlroy had back-to-back double bogeys at the 12th and 13th while Olesen was left counting the cost of an 18th-hole double bogey.
If he wins, Stenson will finish the 2014 European Tour season as runner-up to McIlroy in the Race to Dubai.
"To win would be very pleasing as I've had a solid year, but I haven't got a trophy yet," Stenson said. "There is still a lot of golf to play and Rafa, he's had a 64 and a 65, so he seems to be on fire."
The 30-year-old Cabrera-Bello, who had an opening round 73, is no stranger to winning in Dubai after capturing the Dubai Desert Classic title in 2012.
"The round was a little bit crazy, because I haven't felt I've played perfect at all," Cabrera-Bello said. "I had to work really, really hard, especially at the beginning but I managed to hang in there and end up shooting 3 under on the front nine when I could have easily shot 2 or 3 over."
Lee Janzen scrambled to a par 72, dropping into a share of the lead with Andrew Putnam, who shot a 2-under during a rainy third round of the Callaway Pebble Beach Invitational.
Janzen, a two-time
Tommy Armour, a late entrant who won the event in 2007 and 2008, is alone in third at 9 under following a 66 at Del Monte.
Hall of Famer
Julieta Granada has a one-shot lead going into the final round of the CME Group Tour Championship. Just as close is a four-player race for $1 million.
Granada had four birdies in her round of 2-under 70. Morgan Pressel and Carlota Ciganda of Spain each made big putts on the 18th hole to stay one shot behind. Pressel made a 5-foot birdie putt for a 70. Ciganda made an 8-foot putt for par and a 71.