Sahih al-Bukhari 388
صحيح البخاري#388SahihNarrated Al-Mughira bin Shu'ba: I helped the Prophet (ﷺ) in performing ablution and he passed his wet hands over his Khuffs and prayed
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 8:40