That is not quite what I said. I said I would take a crashing bug over a logic bug. Logic bugs are hard to find because you can't easily test for them. IME, Security vulnerabilities are primarily about functions assuming the input is safe (logic bugs), or file format parsing bugs (logic bugs) or the function being buggy to the point where the caller can poison the stack and/or control EIP. (logic bugs)

For each of these types there are some mitigations available at both the OS and hardware level, but I was making a general point about logic vs crashing bugs.

> If it crashes there's a distinct possibility that the bug is exploitable.

What I mean by crashing is that the program stops executing. Are you saying that crashing bugs make it easier to plant resident code? I'm nota security expert, so I don't quite know what you're referring to.