Sahih Muslim 2655
صحيح مسلم#2655SahihThis hadith has been narrated on the authority of Zuhri with the same chain of transmitters that be heard Allah's Apostle (ﷺ) as saying on a similar day:I am fasting today, so he who wishes to observe fast should do so; but he did not make mention of the rest of the hadith
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: 13:161