Hadith 46

Bulugh al-Maram

Book 8: Marriage
وَصَحَّ عَنِ ابْنِ عَبَّاسٍ عِنْدَ اَلْبُخَارِيِّ ; أَنَّهُ كَانَ عَبْدًا 1‏ .‏
It has been authentically reported from Ibn 'Abbas (RA) by al-Bukhari:

"...that he was a slave".