it's the weasel genus, not family, and the least weasel(a species of the weasel genus) is also referred to just as weasel, and that is what this animal is. It's definitely not a ferret. Ferrets are much larger and their colouring is different, and besides that they are also domesticated.
It's also not a stoat because the tail(seen at 0:29
) isn't bushy enough and lacks the black tip. It's also a bit small for a stoat.