They have various cursewords for white people / foreigners. Kinda hard to translate, though. Most of them don't have direct english translations that would appear insulting in English. Korean is a language where words are different depending on whether you are talking up to someone, like talking to your boss or teacher or the president, and different words for talking down to someone like your child or someone you think is less than human. English doesn't have that so none of it makes sense in English.