Musnad Abu Ya'la al-Mawsili 152:276

Abu Khaythama narrated to us, Hisham ibn Abd al-Malik narrated to us, Abu 'Awanah narrated to us, from Simak, from Abd al-Rahman ibn Abd Allah ibn Mas'ud, from his father, who said: The Messenger of Allah (may Allah bless him and grant him peace) cursed the consumer of usury, the one who pays it, its two witnesses, and its scribe.