Sahih al-Bukhari 2435
صحيح البخاري#2435SahihNarrated Ibn `Umar:Allah's Messenger (ﷺ) said, "An animal should not be milked without the permission of its owner. Does any of you like that somebody comes to his store and breaks his container and takes away his food? The udders of the animals are the stores of their owners where their provision is kept, so nobody should milk the animals of somebody else, without the permission of its owner
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: 45:10