Sahih Muslim 697
صحيح مسلم#697SahihIbn 'Abbas reported it from 'Ali:We sent al-Miqdad b. al-Aswad to the Messenger of Allah (ﷺ) to ask him what must be done about prostatic fluid which flows from (the private part of) a person. The Messenger of Allah (ﷺ) said: Perform ablution and wash your sexual organ
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 3:19