Sahih Muslim 686
صحيح مسلم#686SahihA'isha, the wife of the Apostle (may peace he upon him), reported:The Messenger of Allah (ﷺ) put out from the mosque his head for me as he was in I'tikaf, and I washed it in the state that I was menstruating
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: 3:8