Sylius: Cart FormComponent allows modification or deletion of an already-completed order

Sylius is an Open Source eCommerce Framework on Symfony. Versions 2.0.0 through 2.0.17, 2.1.0 through 2.1.14, and 2.2.0 through 2.2.5 contain an improper workflow enforcement vulnerability in the cart `FormComponent`. When an order is completed while its cart page remains open, the stale LiveComponent does not detect the order’s changed state and continues to permit cart actions, allowing an authenticated customer to modify or permanently delete an already completed order. Versions 2.0.18, 2.1.15, and 2.2.6 contain a patch. As a workaround, deployments can copy the patched `FormComponent` into the application's `src/` directory and override the `sylius_shop.twig.component.cart.form` service definition to use that class.