Sahih al-Bukhari 5905
صحيح البخاري#5905SahihNarrated Qatada:l asked Anas bin Malik about the hair of Allah's Messenger (ﷺ). He said, "The hair of Allah's Messenger (ﷺ) was neither much straight, nor much curly, and it used to hang down till between his shoulders and his earlobes
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: 77:122