Jami` at-Tirmidhi 12
جامع الترمذي#12Da'ifAishah said:"Whoever narrated to you that the Prophet would urinate while standing; then do not believe him. He would not urinate except while squatting." [He said:] There are narrations on this topic from Umar, Buraidah, [and Abdur-Rahman bin Hasanah]
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniDaif
Bashar Awad MaaroufDaif
Zubair Ali ZaiDaif
In-book reference: 1:12