Police say he's about 5'2" and in his late 20s. At the time, he wore a black sweater with a white shirt and bluejeans. He spoke to the victim in Spanish.
Police say a good Samaritan heard the commotion after the guy jumped the woman and managed to scare him off.
If he looks familiar, contact A-7 detectives at 617-343-4234 or the anonymous tip line by calling 800-494-TIPS or texting TIP to CRIME (27463).