Warren, who led overnight, hit three bogeys and a triple bogey on the last six holes in Kuala Lumpur as his three-over round left him on six under.
Bernd Wiesberger leads on 12 under after his second round 63 included nine straight birdies.
England's Danny Willett carded a 67 and is one shot behind Wiesberger.
Willett, the 2016 Masters champion, hit six birdies and a bogey in his second round.
"I played really well on Thursday and it was a little bit scrappy," said Willett.
"I holed a couple of nice putts when I needed to. I missed a couple of good chances too, but if someone told me at the start of the day (you will post) five under, I would have bitten their hand off.
"The last few weeks I've been trying to hit a fade and I've been hitting them straight left and getting in all sorts of problems, so everything has come on nicely.
"But I've been working hard so it's nice to do it on the course."
Scotland's Marc Warren lost the lead of the Maybank Championship after a second round of 75, while England's Danny Willett moved a shot off first place.