GHSA-6vh2-wg4h-4vwj: Flowise: Unauthenticated Property Injection into Flow Execution Context via Ungated `overrideConfig` Spread in Prediction API

Flowise has a security vulnerability in its unauthenticated prediction API endpoint where an attacker can inject arbitrary properties through an `overrideConfig` object (a set of configuration overrides) into the flow execution context without proper access checks. This allows attackers to manipulate chat sessions, steal conversation history, and inject malicious values into template variables that flow nodes use, even though a similar vulnerability was supposedly fixed in an earlier patch.