Police released a sketch of the suspect Thursday.
It happened at the Tanger Outlet mall in Riverhead around noon on Tuesday.
Police say the attacker was hiding in a stall of a ladies room.
As the 67-year old woman exited her stall, the suspect pushed her back into the stall, got behind her placing one of his arms around her neck, and tried to force her to the floor.
The victim was screaming for help when another woman entered the bathroom.
The second woman left the bathroom and notified personnel at a nearby store that there was a woman being attacked in the ladies public restroom.
The suspect fled the scene on foot towards River Road.
The victim suffered cuts and bruises to her face, but was not seriously hurt.
The suspect is described as a young looking black male, clean shaven, about 5'6" to 5'8" tall, slim build, last seen wearing a dark colored hoodie.
Anyone with information is asked to contact Riverhead Police at 631-727-4500.
Police say security at the mall is now being stepped up. But they believe it is a random, isolated incident, and was not part of any larger, regional pattern.