The Shanghai Shenhua-based Cahill scored the second goal for Australia just after half-time following a 40th-minute penalty by skipper Mile Jedinak and finished off by a 69th-minute own goal from defender Ildar Amirov.
The Australians moved to within one point of inactive leaders Jordan in Group B and face Bangladesh in Dhaka on Tuesday.
The Socceroos turned on the razzle-dazzle with their midfield of Aaron Mooy, Massimo Luongo and substitute Tom Rogic dictating the play and setting up many scoring chances.
"We had a game plan and the boys stuck to it and maybe it could have been a little bit more at the end, but we take the victory and the three points most importantly," Jedinak said.
"Our plan was to keep them under pressure, stay on them, don't sit back, stay on the front foot and we did that really, almost suffocated them."