Is There a 3rd Category of Application Security Tools Beyond Static & Dynamic?

Recently, Clark Coleman asked a very logical question about application security tools:

Can you explain the difference between DAST (Dynamic Application Security Testing) and IAST (Interactive Application Security Testing)? To a novice like me, it would seem that you either analyze a program while it is not running (static) or while it is running (dynamic). Logically, (A) and (not A) cover the possible universe with no room for a third category.

The problem, as usual, is naming. What we call DAST means that an application is scanned with HTTP requests in a quest to reveal vulnerabilities based the HTTP responses generated.  What we call SAST means analyzing application code. Putting the names aside, these two techniques don't nearly cover the possible universe of ways to analyze an application's security.

An alternative way of thinking about the problem...

I wrote an article in 2014 to explain why the terms "static" and "dynamic" are misleading.  I proposed an alternative way to organize your thinking about application security tools.

Instead of  thinking of tools as static or dynamic, click here to hop over to DZone and read my guest blog post and learn how to classify them by what information you have available to make decisions.