The incident occurred at about 1.22 a.m. in the 6200-block of North Fairfield Avenue.
Police said a man armed with a sharp object cut the 65-year-old victim on her head and arm.
The suspect, who police said was dressed in all black, left before officers arrived.
The woman had lacerations to her temple and forearm and was transported to St. Francis Hospital, where she was listed in good condition, police said.
No one is in custody and Area Three detectives are investigating.
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