Sahih al-Bukhari 989
صحيح البخاري#989SahihNarrated Ibn `Abbas:The Prophet (ﷺ) went out and offered a two rak`at prayer on the Day of `Id ul Fitr and did not offer any other prayer before or after it and at that time Bilal was accompanying 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: 13:37