The 29-year-old victim was heading home on a northbound No. 3 train when she was attacked just after 11:10 p.m. at the Wall Street stop.
The suspect was apparently trying to steal her cell phone.
The victim was slashed in the left arm, left elbow, back and fingers. The woman was taken to Bellevue Hospital and was said to be stable.
The victim's sister spoke out Thursday and said her sister is a brave woman who is recovering from surgery after fighting back against her attacker.
"The police said they were very impressed by her strength," the victim's sister Michelle said.
The attacker fled the scene. He was last seen wearing a blue face mask and gray backpack.
So far, no arrests have been made in this incident. However, police were able to make an arrest in a separate stabbing at a subway station in Chelsea.
Police charged 21-year-old Carlos Rivera with attempted murder and three charges of felony assault.
Officers responded to the Eighth Avenue and West 23rd Street station in Chelsea at 6:30 p.m. Tuesday, where they found a 25-year-old woman stabbed on the left side of her back.
Police say the victim was walking into the station, down the stairs, when she was approached by Rivera who stabbed her.
The victim was taken to Bellevue Hospital where she's expected to recover.
Police say felony assaults in transit are up 7.4% compared to last year and robberies are down 8.8% compared to last year.
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