The 32-year-old pace bowler has been ruled out of the upcoming white-ball series against New Zealand and India after scans revealed signs of lumbar bone stress in his back.
"(I'm) confident we'll do the rehab right and give it a good crack," Cummins told reporters in Brisbane on Wednesday.
"This far out, it's hard to know, but we're trying to make sure we're doing everything right to be right for Perth.
"It's a big Ashes series, it doesn't get much bigger, so you're willing to be aggressive and take a few risks to try to play as many of the Tests as you can."
Cummins said he had been taking it easy since returning sore from Australia's 3-0 Test triumph over West Indies in June and July.
"With bone injuries, you really just want to settle it down," he said.
"I'm still doing a bit of gym, but no real running, no bowling. Get that right, and then we'll build up to the summer. We've got loads of time, there's about 12 weeks until the first Test. We'll see how the next little bit pans out."
Cummins said his experience should help him hit the ground running when he does get the okay from medical staff to return to bowling.
"At this stage of my career, I feel like I can probably get up to speed a bit quicker than when I was 18 or 19," he added.
"I'm pretty confident even if I don't get a chance to play a (Sheffield) Shield game, I can get up to speed."
Australia begin the defence of the Ashes at Perth Stadium on November 21st with further Tests in Brisbane, Adelaide, Melbourne and Sydney in December and January.