MaxKB: Webhook Trigger Authentication Bypass

MaxKB is an open-source AI assistant for enterprise. Prior to 2.9.0, MaxKB's webhook trigger endpoint (/api/trigger/v1/webhook/{trigger_id}) is accessible without authentication. The WebhookAuth class unconditionally returns (None, {}), which Django REST Framework interprets as successful authentication. Combined with optional per-trigger token verification and no backend enforcement of token requirements, any unauthenticated attacker who knows a valid trigger ID can invoke webhook triggers to execute their bound tasks. This vulnerability is fixed in 2.9.0.