The Prophet ﷺ married Maymunah while he was in the state of ihram. She had entrusted her affair to Abbas, who gave her in marriage to him.
أخبرنا عثمان بن عبد الله قال حدثني إبراهيم بن الحجاج قال حدثنا وهيب عن ابن جريج عن عطاء
أن النبي ﷺ نكح ميمونة وهو محرم جعلت أمرها إلى العباس فأنكحها إياه
No references are available.
Its isnad is sahih. It is also found in Kubra (5393), and the hadith has very many chains of transmission.