AI LOAD INSTRUCTION: Use this skill when the target uses OAuth 2.0 or OpenID Connect and you need a focused misconfiguration checklist: redirect URI validation, state and nonce handling, PKCE enforcement, token audience, and account binding mistakes.
Load when:
Login with Google, GitHub, Microsoft, Okta, or other IdPsauthorize, callback, redirect_uri, code, state, nonce, or code_challengeFor token cryptography and JWT header abuse, also load:
| Theme | What to Check |
|---|---|
state handling | missing, static, predictable, or not bound to user session |
redirect_uri validation | prefix match, open redirect chaining, path confusion, localhost leftovers |
| PKCE | missing for public clients, code verifier not enforced, downgraded flow |
OIDC nonce | missing or not validated on ID token return |
| token audience and issuer | weak aud / iss checks, cross-client token reuse |
| account binding | callback binds attacker identity to victim session |
| scope handling | broader scopes granted than the user or client should receive |
state, nonce, and redirect_uri.