Sahih al-Bukhari 4384
صحيح البخاري#4384SahihNarrated Abu Musa:My brother and I came from Yemen (to Medina) and remained for some time, thinking that Ibn Masud and his mother belonged to the family of the Prophet (ﷺ) because of their frequent entrance (upon the Prophet) and their being attached to him
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: 64:407