Hmm, I'm not sure if we need one. 
It's an important thing about computers. I like the suggestion, but I don't see the need as the community isn't talking about security-related matters to a point it needs its own category.
The only topic I'd consider a security issue is this:
My questions:
- Where would we put it?
- Do we need one?
- Are there any existing topics that are related to security?
- What sort of topics would this section contain?