buskngt,
IF this is an actual attack by a HEALTHY cougar, it's the first one in many years in the "lower 48".
As a TX Master Naturalist, I know of one other case & that one was a female defending her kittens.
Yours, satx
While not common, they do happen on occasion, particularly in California. Here's a listing of verified attacks in CA (including a couple of fatal ones). The 2004 fatality is the one I was thinking of. It was some guy riding his mountain bike when the mountain lion attacked and killed him. The cat was eventually hunted down and killed.