Red buff smite bug

Here you see a Lee Sin top trying to take my red buff (he doesn't have smite). I walk towards him and smite the red buff. You can see the red smite animation and the cooldown on my smite. My smite deals 680 dmg and the red buff has less health than that, but Lee gets the red buff. After that I aa'd Lee and although I don't have red buff, I still apply red buff on him.