As a CFO of a company, are you legally responsible for any and all of the companies finances?

I assume that this "$20 + mil company" is a separate legal entity, such as a corporation, or llc.  Officers and employees of such an entity are not responsible for the corporation's obligations, nor, in most cases, are shareholders.  As with any employee, however, a CFO could potentially be liable (most often to shareholders) for his personal actions taken on behalf of the corporation.  For example, if you sign off on a fraudulent financial statement which a bank relies on in loaning money to the company, you could be personally liable for that fraud. As for whether there are "any other potential legal issues", that is just too broad,.  There are many potential legal issues which may be implicated by your position, depending on the particular facts, ranging from possible liability from signing securities filings, liability for violation of securities laws if the company releases misleading information into the marketplace, potential insider trading problems, obligations not to usurp corporate opportunities, etc.