Studies show that 82% of mold species are killed by vinegar. However, it can leave your humidor (and cigars stored in there) smelling like a salad. Peroxide (an oxidizer) is compatible with vinegar (unlike bleach) so you don't have to worry about unfortunate reactions. In fact, you can even mix them together for added power. We use acetic (vinegar) along with an oxidizer as a cleanup method for stubborn contaminants.