Kabsha daughter of Ka‘b b. Malik and wife of Ibn Abu Qatada said that Abu Qatada visited her and she poured out water for him for ablution. A cat came and drank some of it, and he tilted the vessel for it till it had had a drink. Kabsha said that when he saw her looking at him he asked, “Are you surprised, my niece?” When she replied that she was, he declared that God’s messenger said, “It is not unclean; it is one of those who go round among you.” Malik, Ahmad, Tirmidhi, Abu Dawud, Nasa’i, Ibn Majah and Darimi transmitted it.
Source: sunnah.com
Other translations
Arabic
وَعَن كَبْشَة بنت كَعْب بن مَالك وَكَانَتْ تَحْتَ ابْنِ أَبِي قَتَادَةَ: أَنَّ أَبَا قَتَادَة دخل فَسَكَبَتْ لَهُ وَضُوءًا فَجَاءَتْ هِرَّةٌ تَشْرَبُ مِنْهُ فَأَصْغَى لَهَا الْإِنَاءَ حَتَّى شَرِبَتْ قَالَتْ كَبْشَةُ فَرَآنِي أَنْظُرُ إِلَيْهِ فَقَالَ أَتَعْجَبِينَ يَا ابْنَةَ أخي فَقُلْتُ نَعَمْ فَقَالَ إِنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «إِنَّهَا لَيست بِنَجس إِنَّهَا من الطوافين عَلَيْكُم والطوافات» . رَوَاهُ مَالِكٌ وَأَحْمَدُ وَالتِّرْمِذِيُّ وَأَبُو دَاوُدَ وَالنَّسَائِيُّ وَابْنُ مَاجَهْ وَالدَّارِمِيُّ
sunnah.com