CVE-2026-31820: Authorization Bypass Through User-Controlled Key

Sylius is an Open Source eCommerce Framework on Symfony. An authenticated Insecure Direct Object Reference (IDOR) vulnerability exists in multiple shop LiveComponents due to unvalidated resource IDs accepted via #[LiveArg] parameters. Unlike props, which are protected by LiveComponent's @checksum, args are fully user-controlled - any action that accepts a resource ID via #[LiveArg] and loads it with ->find() without ownership validation is vulnerable. Checkout address FormComponent (addressFieldUpdated action): Accepts an addressId via #[LiveArg] and loads it without verifying ownership, exposing another user's first name, last name, company, phone number, street, city, postcode, and country. Cart WidgetComponent (refreshCart action): Accepts a cartId via #[LiveArg] and loads any order directly from the repository, exposing order total and item count. Cart SummaryComponent (refreshCart action): Accepts a cartId via #[LiveArg] and loads any order directly from the repository, exposing subtotal, discount, shipping cost, taxes (excluded and included), and order total. Since sylius_order contains both active carts (state=cart) and completed orders (state=new/fulfilled) in the same ID space, the cart IDOR exposes data from all orders, not just active carts. The issue is fixed in versions: 2.0.16, 2.1.12, 2.2.3 and above.