Sunan Ibn Majah
2789
Sahih+3

It was narrated from Abu Qatadah Al-Ansari that the Messenger of Allah (ﷺ) said:“The best of horses are those that are deep black, with a blaze on the forehead, white marks on the legs and white nose and upper lip, and with no whiteness on the right foreleg. If not deep-black, then reddish-brown, with these markings.”

SahihAl-Albani
SahihMuhammad Fouad Abd al-Baqi