The Prophet ﷺ said, "When one of you rises from sleep at night, he should not dip his hand into his vessel until he washes it three times, for he does not know where his hand spent the night."
حدثنا عبد الأعلى عن معمر عن الزهري عن أبي سلمة
أن النبي ﷺ قال إذا قام أحدكم من الليل فلا يغمس يده في إنائه حتى يغسلها ثلاثا فإنه لا يدري أين باتت يده
Its isnad is sahih, and it is a repetition of 7280, 7432, 7432m, 7433. We have already covered its narrations, including this one, previously. Nasai narrated it in 1:37 through the route of Mamar from Zuhri. He also narrated it in 1:41 through the route of Sufyan from Zuhri, with the same chain. He also narrated it in 1:75 through the route of Uzai from Zuhri from Saeed bin Musayab from Abu Hurairah.