Sahih al-Bukhari 2447
صحيح البخاري#2447SahihNarrated Ibn `Umar:The Prophet (ﷺ) said, "Oppression will be a darkness on the Day of Resurrection
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: 46:8