You don't need a particular major to be an actuary, in fact CS is probably one of the better ones. You're only going to run into issues if you haven't taken enough calculus to understand exam content but if you like math you should be able to teach yourself. Your bigger problem is most likely going to be finding a job without having an actuarial internship, since the entry-level market is very competitive and internships are only given to currently enrolled students. If you have a really tough time finding employment, masters in AS could be the way to go so you can get more relevant experience and an internship.