Musnad Abu Ya'la al-Mawsili 115:200

Muhammad ibn Mahdi narrated to us, Abd al-Razzaq narrated to us, Ma'mar informed us, from Qatadah, from Anas, who said: The Messenger of Allah (ﷺ) was cupped while he was in the state of Ihram on the top of his foot, due to a pain he had.