McCullum, who will be retiring from the game after the second Test against Australia in February, has been out of action since December after aggravating his back in the ODIs against Sri Lanka.
Black Caps coach Mike Hesson said: “He’s progressing really well and doing plenty of work away from the game, from a fitness point of view and we’re really pleased with the way he’s tracking.
“Hopefully he’ll play a part in the Pakistan series and if he does that will be good prep for the Chappell-Hadlee (series v Aus) and beyond.”
Another lower back concern is all-rounder Corey Anderson, who picked up a stress fracture against England last year, and has been playing as a batsman for a while, though has started to bowl in matches again.
Hesson said of Anderson: “I’m delighted how he’s coming along and he’s certainly confident with the body. We’ve gone pretty slow with it to make sure that we give him the best chance of being back for a long period.
“I’m really pleased to give him a chance with the new ball and even happier that he took it.
“We’ll just keep managing it. It [Test cricket] is not something we’re going to push. We’ve got some pretty clear loads in place to give him a chance of being on the park a lot longer.
“We’ve got some one-day cricket coming up and we’re hopeful he’ll be in a position to be able to play a decent role in those.”
Hesson also addressed the fitness of fast bowler Tim Southee, who has been Missing In Action due to a foot injury, and will hopefully be back for the Tests against the Australians.
The coach added: “Tim is progressing nicely and he’ll be with us this week [in Wellington] to help work with his rehab. He’s unlikely [to play the Australia ODIs].
“We’ll focus on the Test series at this stage and make sure that he’s firing. We certainly won’t force him playing any games earlier than that unless we need him. He could well play a Plunket Shield game to get him ready for the Tests.”