Kabshah bint Ka'b bin Malik, who was the wife of Abu Qatadah (may Allah be pleased with him) or one of his sons, narrates: Abu Qatadah (may Allah be pleased with him) came, so I placed a vessel for his ablution. A cat came and drank water from that vessel. She says: Abu Qatadah (may Allah be pleased with him) saw me looking at it with astonishment, so he said: "Are you astonished, O my niece? Indeed, the Messenger of Allah (ﷺ) said: 'It is not impure. It is among those (creatures) that go around among you.'"
Hadith Referenceمسند الإمام الشافعي / كتاب الطهارة / 7
Hadith Takhrijأخرجه الترمذي: الطهارة، باب ماجاء في سؤر الهرة: (92) - وقال ”حسن صحيح“ وابوداؤد، الطهارة، باب سؤر الهرة (75) و ابن ماجة، الطهارة، باب الوضوء بسؤر الهرة والرخصه في ذلك: (367) وصححه ابن الجارود: (60) وابن خزيمة: (104). والحاكم: 159/1، 160.