CVE-2026-68500

Sylius Mollie Plugin vulnerable to payment status forgery via the payment webhook

The shop payment webhook POST /{_locale}/update-payment (route
sylius_mollie_shop_payment_webhook) accepts two independent, attacker-controlled
parameters: id (the Mollie payment ID, verified against Mollie's API) and orderId (the
Sylius order ID, read directly from the database). The handler never verifies that the
Mollie payment belongs to the referenced order.

An unauthenticated attacker who holds any valid paid Mollie payment ID, for example
from a EUR 1 order they placed themselves, can submit it together with any victim
orderId. The victim's order payment is then transitioned to completed (or any other
Mollie-derived state) without any funds being transferred for that order. Sylius order IDs
are sequential integers, and the endpoint requires no authentication, CSRF token or rate
limiting, so the attack scales trivially across all pending orders.

Patches

Fixed in versions 2.2.8, 3.2.4 and 3.3.1. The webhook now binds the payment to
the order: it reads the Mollie payment ID stored server-side for that order when the payment
was created and compares it to the incoming Mollie payment ID. On mismatch the request is
acknowledged with HTTP 200 and no state change is applied. HTTP 200 is intentional,
because Mollie retries the webhook on any non-2xx response.

The stored ID lives in one of two places depending on the checkout flow, and the fix reads
both of them (mirroring CaptureAction):

• payment.getDetails()['payment_mollie_id'] for the standard Shop API and Apple Pay Direct
  flows, stored in CreatePaymentAction.
• order.getMolliePaymentId() for the QR-code flow, which stores the ID on the order itself
  (QrCodeAction).

Reading only the payment details would reject legitimate QR-code payments, because their
payment details carry no payment_mollie_id, so both sources must be consulted.

Workarounds

If you cannot upgrade immediately, patch the vulnerability at the project level by
decorating the plugin's webhook controller. The decorator checks that the incoming Mollie
id matches the id stored for that order before handing over to the original controller,
so no plugin behaviour (state machine, logging) is lost and no extra Mollie API call is
made. Works on both 2.2 and 3.x.

Step 1. Create the decorator

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

<?php

declare(strict_types=1);

namespace App\Controller\Mollie;

use Sylius\Component\Core\Model\OrderInterface;
use Sylius\Component\Order\Repository\OrderRepositoryInterface;
use Sylius\MolliePlugin\Controller\Shop\PaymentWebhookController;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

final class SecurePaymentWebhookController
{
    public function __construct(
        private readonly PaymentWebhookController $inner,
        private readonly OrderRepositoryInterface $orderRepository,
    ) {
    }

    public function __invoke(Request $request): Response
    {
        $orderId = $request->get('orderId');
        $molliePaymentId = $request->get('id');

        if (null === $orderId || null === $molliePaymentId) {
            return ($this->inner)($request);
        }

        /** @var OrderInterface|null $order */
        $order = $this->orderRepository->findOneBy(['id' => $orderId]);
        if (null === $order) {
            return ($this->inner)($request);
        }

        $storedMollieId = $this->resolveStoredMollieId($order);

        // Reject any webhook whose Mollie id does not match the one stored for this order.
        // 200 is intentional: Mollie retries on any non-2xx response.
        if (null === $storedMollieId || $storedMollieId !== (string) $molliePaymentId) {
            return new JsonResponse(null, Response::HTTP_OK);
        }

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

    private function resolveStoredMollieId(OrderInterface $order): ?string
    {
        $payment = $order->getLastPayment();
        $fromDetails = $payment?->getDetails()['payment_mollie_id'] ?? null;
        if (null !== $fromDetails && '' !== $fromDetails) {
            return (string) $fromDetails;
        }

        // QR-code flow stores the Mollie id on the order itself.
        if (method_exists($order, 'getMolliePaymentId')) {
            $fromOrder = $order->getMolliePaymentId();
            if (null !== $fromOrder && '' !== $fromOrder) {
                return (string) $fromOrder;
            }
        }

        return null;
    }
}

Step 2. Register the decorator

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

services:
    App\Controller\Mollie\SecurePaymentWebhookController:
        decorates: sylius_mollie.controller.shop.payment_webhook
        public: true
        arguments:
            $inner: '@.inner'
            $orderRepository: '@sylius.repository.order'

decorates: keeps the original service ID, so the route
_controller: sylius_mollie.controller.shop.payment_webhook keeps working with no route
changes. @.inner is the original plugin controller.

Step 3. Clear the cache

bin/console cache:clear

CVE-2026-68500 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (2.2.8, 3.2.4, 3.3.1); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

1. What is CVE-2026-68500? CVE-2026-68500 is a high-severity security vulnerability in sylius/mollie-plugin (composer), affecting versions < 2.2.8. It is fixed in 2.2.8, 3.2.4, 3.3.1.
2. How severe is CVE-2026-68500? CVE-2026-68500 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of sylius/mollie-plugin are affected by CVE-2026-68500? sylius/mollie-plugin (composer) versions < 2.2.8 is affected.
4. Is there a fix for CVE-2026-68500? Yes. CVE-2026-68500 is fixed in 2.2.8, 3.2.4, 3.3.1. Upgrade to this version or later.
5. Is CVE-2026-68500 exploitable, and should I be worried? Whether CVE-2026-68500 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-68500 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-68500?
   • Upgrade sylius/mollie-plugin to 2.2.8 or later
   • Upgrade sylius/mollie-plugin to 3.2.4 or later
   • Upgrade sylius/mollie-plugin to 3.3.1 or later

Other vulnerabilities in sylius/mollie-plugin