A woman was stabbed in the back in an unprovoked attack on a Sheepshead Bay street Monday morning, cops said. 

The Brooklyn assailant did not say a word during the attack and was last seen pushing a shopping cart, cops said. 

The victim, described as in her 30s, was walking on Batchelder Street near Avenue X around 9:20 a.m. when the other woman attacked her with a “sharp instrument,” police said. 

The victim was taken to NYU Langone Brooklyn Hospital, where she is listed in stable condition. 

It was unclear whether the victim and suspect knew each other.