Sunan Ibn Majah 353
سنن ابن ماجه#353SahihIt was narrated that Ibn 'Umar said:"A man passed by the Prophet while he was urinating and greeted him with the Salam, and he did not return the greeting
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniHasan Sahih
Muhammad Fouad Abd al-BaqiHasan Sahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 1:87