Is it permissible to enter an abandoned, uninhabited house in Iraq without the knowledge of its unknown owner and sit in it?

It is not permissible for a Muslim to use another's property without their permission, even if the house is empty. The fundamental principle regarding property is its inviolability, based on the Prophet's (peace and blessings be upon him) saying: "Indeed, your blood, your property, and your honor are sacred to you."