Sylius Mollie Plugin has unauthenticated IDOR that leaks order token and customer PII

Impact

Two unauthenticated Mollie shop endpoints look up orders by a sequential integer orderId with no ownership or session check. Chained, they expose customer PII.

GET /{_locale}/thank-you (PageRedirectController::thankYouAction, route sylius_mollie_shop_thank_you_page_redirect) loads the order with findOneBy(['id' => $orderId]) and returns a 302 whose Location header carries that order's tokenValue. Any orderId thus yields that order's token. A non-existent id dereferences null and returns a 500. The handler also writes the raw orderId into the session.

GET /{_locale}/get-code (QrCodeAction::fetchQrCodeFromOrder, route sylius_mollie_shop_get_qr_code) runs the same lookup and returns the order's QR code and id as JSON, ignoring the session cart; this is where the front-end got the integer id. A bad id 500s here too.

That tokenValue is the order's only access control. Passed to the Sylius core page GET /{_locale}/register-after-checkout/{tokenValue} it returns a form pre-filled with the customer's first name, last name and email. The full attack: enumerate orderId, read the token from the redirect, read the PII, at roughly a 1-in-71 hit rate for guest orders. register-after-checkout is Sylius core, not the plugin, and trusts the token by design, so the leak is what must be fixed.

None of the plugin endpoints require a login, session or CSRF token.

Patches

Fixed in 2.2.8, 3.2.4 and 3.3.1.

Workarounds

If you cannot upgrade immediately, patch both endpoints at the project level by decorating the plugin controllers. The decorators enforce ownership before delegating to the original controller, so no plugin behaviour is lost. They keep the original orderId request contract, so no front-end or asset changes are required. Works on both 2.2 and 3.x.

Step 1. Decorate the QR code controller

Create src/Controller/Mollie/SecureQrCodeAction.php in your Sylius project:

<?php

declare(strict_types=1);

namespace App\Controller\Mollie;

use Sylius\Component\Order\Context\CartContextInterface;
use Sylius\Component\Order\Context\CartNotFoundException;
use Sylius\MolliePlugin\Controller\Shop\QrCodeAction;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

final class SecureQrCodeAction
{
    private const OWNED_ORDER_IDS_SESSION_KEY = 'sylius_mollie.owned_order_ids';

    public function __construct(
        private readonly QrCodeAction $inner,
        private readonly CartContextInterface $cartContext,
    ) {
    }

    public function fetchQrCodeFromOrder(Request $request): JsonResponse
    {
        $orderId = $request->get('orderId');

        try {
            $cart = $this->cartContext->getCart();
        } catch (CartNotFoundException) {
            $cart = null;
        }

        if (null !== $orderId && (null === $cart || (string) $cart->getId() !== (string) $orderId)) {
            return new JsonResponse([], Response::HTTP_FORBIDDEN);
        }

        if (null !== $cart && null !== $cart->getId() && $request->hasSession()) {
            $session = $request->getSession();
            $ownedIds = $session->get(self::OWNED_ORDER_IDS_SESSION_KEY, []);
            $ownedIds[(string) $cart->getId()] = true;
            $session->set(self::OWNED_ORDER_IDS_SESSION_KEY, $ownedIds);
        }

        return $this->inner->fetchQrCodeFromOrder($request);
    }

    public function createPayment(Request $request): Response
    {
        return $this->inner->createPayment($request);
    }

    public function removeQrCodeFromOrder(Request $request): JsonResponse
    {
        return $this->inner->removeQrCodeFromOrder($request);
    }
}

Step 2. Decorate the thank-you controller

Create src/Controller/Mollie/SecurePageRedirectController.php:

<?php

declare(strict_types=1);

namespace App\Controller\Mollie;

use Sylius\MolliePlugin\Controller\Shop\PageRedirectController;
use Symfony\Component\HttpFoundation\RedirectResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Session\SessionInterface;
use Symfony\Component\Routing\RouterInterface;

final class SecurePageRedirectController
{
    private const OWNED_ORDER_IDS_SESSION_KEY = 'sylius_mollie.owned_order_ids';

    public function __construct(
        private readonly PageRedirectController $inner,
        private readonly RouterInterface $router,
    ) {
    }

    public function thankYouAction(Request $request, SessionInterface $session): RedirectResponse
    {
        $orderId = $request->get('orderId');

        if (null !== $orderId) {
            $ownedIds = $session->get(self::OWNED_ORDER_IDS_SESSION_KEY, []);

            if (!isset($ownedIds[(string) $orderId])) {
                return new RedirectResponse($this->router->generate('sylius_shop_cart_summary'));
            }
        }

        return $this->inner->thankYouAction($request, $session);
    }
}

Step 3. Register the decorators

Append to your project's config/services.yaml:

services:
    App\Controller\Mollie\SecureQrCodeAction:
        decorates: sylius_mollie.controller.shop.qr_code
        public: true
        arguments:
            $inner: '@.inner'
            $cartContext: '@sylius.context.cart'

    App\Controller\Mollie\SecurePageRedirectController:
        decorates: sylius_mollie.controller.shop.page_redirect
        public: true
        arguments:
            $inner: '@.inner'
            $router: '@router'

Both decorators keep @.inner and only add an ownership check on orderId before handing the request to the original action, so createPayment, removeQrCodeFromOrder and the thank-you redirect all keep their original behaviour and the front-end contract is unchanged.

Step 4. Clear the cache

bin/console cache:clear