Tara Moss attacked in Sydney

Crime writer and model Tara Moss is nursing a few bruises after being attacked by a "drug affected" man in Sydney's CBD.

Moss was physically assaulted by a man on Market St while heading towards Hyde Park.

"Was just hit by a man in the street. He's on Market St in dark clothing headed toward Hyde Park. Slim/white. Beware. Suspect drug affected," Moss tweeted on Wednesday.

The Canadian-born author took to Twitter shortly after the attack to alert people.

"He was in dark casual clothing, perhaps 6ft, travelling alone. Don't approach as I suspect he is drug affected," she wrote.

Moss has spoken to police and has been told the man fits the description of a known perpetrator.

"Random attack. Police are looking for him."

"In the meantime be careful the Hyde Park/CBD area," Moss wrote.

The 40-year-old mother of one has been a strong advocate for fighting violence against women.

She was recently in the spotlight after appearing on the ABC's Q&A program where she broke her silence over her own experience of sexual assault and rape.

Police are still making inquiries around the CBD scene and are appealing for witnesses to come forward.

Moss, who is based in Autralia, has written nine novels. In her latest book, The Fictional Woman released in June, Moss takes a more personal route, exploring the challenges facing modern women.