Sayyiduna Uqbah bin Amir (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) say: "A Muslim is the brother of a Muslim. It is not permissible for a Muslim to sell his brother anything that has a defect in it unless he makes it clear to him."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14948