Sahih al-Bukhari 5982
صحيح البخاري#5982SahihNarrated Abu Ayyub Al-Ansari:It was said" "O Allah's Messenger! Inform me of a deed which will make me enter Paradise." (continues through a different chain in the next hadith)
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: 78:13