Hm, C language (itself) hasn't got much major changes since ANSI standardization. I would say that one is able to grasp changes relevant to him, by whipping through the changelog for 10-15 minutes
Edit: If you are critizing K&R for not teaching how to write safest code then, well, you are right. It is simply not meant to do that
You're right on the security part, and that C authors hardly care about it is visible on the language itself, naturally the book wouldn't be any better.
It would of course also increase server's potential attack layer. sqlite had some bugs, potentially exploitable, if you are able to invoke arbitrary statements
Edit: If you are critizing K&R for not teaching how to write safest code then, well, you are right. It is simply not meant to do that