Glossary
Threat Model
A threat model names the adversaries a system is being defended against, what capabilities and access they're assumed to have, and what they would gain from a successful attack. Without one, security work tends to default to whatever the team building it happens to think of, which may miss the adversaries that matter most and over-invest in ones that don't.
A threat model is not a one-time document. A system's real threat landscape shifts as it changes — a new integration point, a new class of user, a new category of automated caller — and a threat model that isn't revisited alongside those changes drifts out of date exactly when it matters most.