Musnad Abu Ya'la al-Mawsili 42:16

Zuhayr narrated to us, Yahya ibn Sa'id narrated to us, from Shu'bah, from Qatadah, from Abu 'Isa al-Aswari, from Abu Sa'id al-Khudri: That the Prophet (peace and blessings of Allah be upon him) forbade drinking while standing.