Sahih Muslim 2674
صحيح مسلم#2674SahihAbu Sa'id al-Khudri (Allah be pleased with him) reported that the Messenger of Allah (ﷺ) forbade to observe fast on two days the day of Fitr and the day of Sacrifice ('Id-ul-Adha)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 13:180