Sunan Abi Dawud 105
سنن أبي داود#105SahihAbu Hurairah reported :I heard the Messenger of Allah (May Peace be upon him) say: When any of you wakes up from sleep, he should not put his hand in the utensil until he washes it three times, for none of you knows where his hand remained during the night or where it went round
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 1:105