Overnight leader Darren Clarke managed a 2-under 70 and is alone in second place at minus-7. Luke Donald (68) and Jim Furyk (70) are knotted in third place at 6-under-par 138.
Ernie Els, who made his return to competitive golf on Thursday after a four-month layoff with a knee injury, shot a 2-under 70 and is tied for seventh place at minus-2.
Cabrera was 2 under par on his round when he made his way to the par-5 ninth. He used a 9-iron to reach the green with his second and two-putted for birdie.
Cabrera birdied three more in a row from the 10th, then parred No. 13. He got the par-5 14th green in two with an 8-iron and birdied that hole. Cabrera birdied the 15th to take his two-shot lead.
Defending champion Retief Goosen posted a 3-under 69 and is alone in fifth place at 5-under-par 139. Adam Scott also carded a 69 on Friday and has sixth at minus-3.
Els and Tim Clark (72) are knotted in seventh, while Chris DiMarco shot a 1-under 71 on Friday and is alone in ninth at minus-1.
Two-time winner Sergio Garcia improved on his opening-round 74 with a 2-under 70 in round two. He is at even-par 144, followed by Kenny Perry who is in 11th place at plus-4.
Stewart Cink rounds out the 12-man field. He struggled to a 4-over-par 76 on Friday and completed two rounds at 5-over-par 149.