The Prophet ﷺ forbade two types of transactions and two manners of dressing.As for the two transactions, they are mulamasa, where a sale is concluded merely by touching the item, and munabadha, where a sale is concluded by tossing the item.As for the two manners of dressing, the first is wrapping oneself in a single garment in the Samma style, and the second is a man sitting with his knees drawn up while wrapped in a single garment, with his private parts exposed or with nothing covering them.
حدثنا قتيبة بن سعيد وأحمد بن عمرو بن السرح وهذا لفظه قالا حدثنا سفيان عن الزهري عن عطاء بن يزيد الليثي
أن النبي ﷺ نهى عن بيعتين وعن لبستين أما البيعتان فالملامسة والمنابذة وأما اللبستان فاشتمال الصماء وأن يحتبي الرجل في ثوب واحد كاشفا عن فرجه أو ليس على فرجه منه شيء
Bukhari narrated it in the chapter on seeking permission, the section on sitting in whatever manner is convenient, no. 6284, from the hadith of Sufyan bin Uyayna, with this wording. Muslim also narrated it, no. 1512, from the hadith of Abu Saeed Khudri, with this wording.