Dublin District Court heard she trespassed at the property when she was not able to get a hostel room.
Murphy, of Haroldville Avenue, Rialto, pleaded guilty to causing criminal damage at Terenure Road West at 8.50pm on November 30 last.
Murphy had a "very significant drug habit" and was now on a methadone programme, her solicitor Maura Kiely said.
Ms Kiely said her client had been in desperate circumstances.
The court heard the accused' wanted to see her children at Christmas and was concerned about being in custody.
Judge Victor Blake gave her several concurrent sentences totalling three months for causing the damage, as well as other charges before the courts.