All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
It is not permissible for anyone to dispose of the property or rights of others without their permission, as that would be an encroachment upon the owner's right. The prohibition here encompasses all types of dealings, whether it's usage, lending, renting, or any similar actions. Allah says in the Quran: "And do not eat up your property among yourselves for vanities." [Al-Baqarah/188]. Imam Al-Baydawi explained this verse as meaning: "That is, do not allow one another to consume each other's property in a manner that Allah has not permitted." [Anwar al-Tanzil vol.1/pp.127].
Imam Al-Shafi'i, may Allah have mercy on him, said: "And it is not permissible for someone who irrigates date palms to cultivate al-Bayadh (a type of crop) except with the permission of its owner. If he does so without the owner's permission, it is as if he has planted in someone else's land." [Mukhtasar al-Muzani vol.8/pp.223].
Indeed, some scholars consider using someone else's property without their knowledge as a form of usurpation, because it involves seizing the property of another without rightful claim. This includes obtaining benefits from the property without the owner's knowledge, as well as utilizing resources that the owner may have left unused for a specific purpose.
Therefore, it is not permissible to use this abandoned house without the permission of its owners. Consequently, anyone who uses it without permission is liable for wrongdoing and accountability under Islamic law. In addition, utilizing someone else's property without rightful claim can subject an individual to questioning and potential consequences, even if their intention was good. And Allah The Almighty Knows Best.