What Is Concept Drift, and Why It's a Silent Security Risk

Models don't tell you when the world has moved on. Here's how drift happens, how attackers use it, and how to catch it.

A model is a snapshot of the data it was trained on. When the world changes, the model keeps answering with the same confidence, and nothing inside it warns you. In fraud, spam, and abuse detection, that gap is something attackers find and use. You catch it by watching inputs and outcomes, not by trusting the model's scores.

A fraud model learns from his…