Tirmidhi 97

[Its chain is daif.] Ibn Majah reported it in the Book of Purification, Chapter on wiping the top and bottom of the leather sock, hadith no. 550, and Abu Dawud, hadith no. 165, from the hadith of Walid through the same chain, and he did not explicitly state hearing it throughout the chain, and Raja did not hear it from the scribe of Mughira. Shafii, Bukhari, Abu Dawud, Abu Hatim, and others graded the hadith daif.