Sahih Muslim 1680
صحيح مسلم#1680SahihHafsa reported:When the dawn appeared, the Messenger of Allah (ﷺ) observed two rak'ahs (of Sunnah prayers)
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: 6:110