Hadith 6:30
Ibn 'Abbas (RAA) narrated, ‘The Messenger of Allah (ﷺ) had himself cupped while he was in the state of Ihram Agreed upon.
وَعَنِ اِبْنِ عَبَّاسٍ رَضِيَ اَللَّهُ عَنْهُمَا; أَنَّ اَلنَّبِيَّ - صلى الله عليه وسلم -{ اِحْتَجَمَ وَهُوَ مُحْرِمٌ } مُتَّفَقٌ عَلَيْهِ
Original Reference: Bulugh al-Maram 737