Al-Imām al-Bukhārī - upon whom be mercy - narrates: ‘Abdullāh ibn Yūsuf narrated to us, from Imām Mālik, from Abū al-Zinād, from al-A’raj,
from Abū Hurayrah (may Allāh Almighty be content with him), who said: The Messenger of Allāh ﷺ said: “When a dog drinks from the vessel of one of you, let him wash it seven times.”
Reference: Sahih Al Bukhari 172