The CX-50 is made in Alabama. I’m not sure if the dealership will do anything about this right now. They might wait until it gets worse.
I have a 12-year rust warranty as long as I get the free check-up every year.
That doesn’t look like true rust to me. I’m not entirely sure what it is, but I’d recommend taking it to your local dealer for a quick look. Could it be fallout? I’m not sure.