Bismillaah:

Shaykh Muhammad At Tihami رحمه الله said:

Such water is also considered pure. This is proven by the hadeeth of Kabshah bint Ka'b who, when she was under the care of Abu Qatadah رضي الله عنه entered the room to pour some water for him. A cat came, drank some of the water, and Qatadah proceeded to tilt the container so the cat could drink more. Kabshah said, "He noticed that I was watching him." He asked, "Are you surprised, O niece?" I answered, "Yes." He said, "The Messenger صلي الله عليه وسلم said, 'It (the cat) is not impure. They intermingle with you."

{ Fiqh Us Sunnah }

*** And Allaah عزوجل knows ***