Messenger of Allah ﷺ said, "If a dog drinks from the utensil of anyone of you it is essential to wash it seven times."  

إِنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا شَرِبَ الْكَلْبُ فِي إِنَاءِ أَحَدِكُمْ فَلْيَغْسِلْهُ سَبْعًا