Sunan an-Nasa'i, 18

It was narrated that Hudhaifah said:"I was walking with the Messenger of Allah (ﷺ) and he came to some people's garbage dump and urinated while standing up. I turned to go away, but he called me back (to conceal him), and I was just behind him. Then when he had finished, he performed Wudu' and wiped over his Khuffs

Rapporté par Hudhaifah : Je marchais avec le Messager d’Allah (ﷺ) et il est arrivé près d’un tas d’ordures de certaines personnes et a uriné debout. J’ai voulu m’éloigner, mais il m’a rappelé (pour le cacher), alors je me suis placé juste derrière lui. Quand il a fini, il a fait ses ablutions et a passé ses mains mouillées sur ses khuffs