The Messenger of Allah ﷺ said, "It is not lawful to sell what you do not possess, nor to profit from what you have not guaranteed."
حدثنا أزهر بن مروان قال حدثنا حماد بن زيد ح و حدثنا أبو كريب حدثنا إسمعيل ابن علية قالا حدثنا أيوب
قال رسول الله ﷺ لا يحل بيع ما ليس عندك ولا ربح ما لم يضمن
Its isnad is sahih. Abu Dawud narrated it in the Book of Sales, the preceding chapter, hadith no. 3504, from the hadith of Ayub, with this wording. Tirmidhi graded it sahih, hadith no. 1234, as did Ibn Jarud, Hakim, and Dhahabi.