>>16689961 (OP) (OP)
your thesis got approved, so you know how to work a research job. just apply to a university or college for that, it's basically what you did until now. Sometimes this helps you land a teaching job as well.
I don't know what kind of math you were doing, but cryptography needs more complicated math than a cs brainlet like me would understand. elliptical curve cryptography, for example, maybe look into that, if you enjoy it.
basically google "fields that require [the field of mathematics your thesis, or your favorite uni project was in]" and start scrolling.
if you're american, consider moving to a country that hasn't cut research funds, maybe some countries even try to paperclip people with phds, there might be money in it for you. they don't have to know that you have no plans for your future yet.