Flowise through 3.1.4 resolves SSO and local-password users solely by email without storing provider or subject identifier bindings, allowing attackers to authenticate as any existing user by claiming their email at any configured SSO provider. Attackers can gain complete account access including chatflows, credentials, and API keys by authenticating through a different SSO provider or local password than the victims original registration method.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.