SureCart < 4.9.5 - Unauthenticated Private Catalog Data Disclosure via 'expand' Parameter

Description

The plugin does not restrict which related objects an anonymous visitor may include when reading a single upsell funnel through its REST API, nor strip private fields from those objects, allowing unauthenticated users to read merchant-private catalog data such as pricing, commission, stock, SKU and tax internals, including unpublished products.