The 33-year-old was on Edinbeg Avenue in the Toryglen area of Glasgow when a man got out of a car and forced her into a common close between midnight and 3am on Saturday.
The man and two other men, who the victim believes were also in the car, then subjected her to a sexual assault.
They fled after the attack. The woman did not require hospital treatment but has been left distressed by the incident, police said.
The three suspects are described as Asian and aged in their twenties.
Officers have been gathering CCTV footage from the area and are following up calls after an initial appeal on Monday.
Detective Chief Inspector Sharon MacGregor said: "We have received an encouraging response from the public following the coverage in the media and I would like to extend my thanks to everyone who contacted us.
"Detectives are now examining that information to establish if there are any new lines of inquiry which can be followed up."
Police are trying to trace the car involved and believe it was a white or silver BMW or similar model.
Ms MacGregor added: "I would still like to appeal to anyone who may have any information or knowledge about the suspects or the incident to get in touch with us as a matter of urgency.
"A small piece of information can be significant so please do pass it on."
Extra police patrols have been deployed in the area following the incident in a bid to reassure people.