Sahih al-Bukhari 1004
صحيح البخاري#1004SahihNarrated Anas:The Qunut used to be recited in the Maghrib and the Fajr 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 al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 14:15