We allow only answers in the answer section, no exceptions. Once you have sufficient reputation, you'll be able to comment everywhere and downvote bad answers.
A very important power that you get pretty early (15 reputation) is the ability to flag posts. If you're sure that an answer is malicious, flag it as needing moderator attention, and fully explain the situation and what you want done. If you're not so certain, you can ask about it in chat, which is open to anybody with 20 reputation or more.
There's also meta (right here!), which anybody with 5 reputation can participate in. It's perfectly acceptable to ask on meta for something to be done when you don't have sufficient privileges to do it yourself.