MDVA-31006 Magento patch: Paypal Duplicate Orders 10415 error

The MDVA-31006 Magento patch fixes the issue where using the PayPal Express checkout payment creates duplicate orders with a 10415 error. This patch is available in the Magento Quality Patches (MQP) tool version 1.0.6. The issue will be fixed in 2.4.2.

Affected products and versions

• This patch is compatible with the following Magento versions and editions:
  Magento Commerce 2.3.2-2.4.0 and Magento Commerce Cloud 2.3.2-2.4.0

Note: the patch can be applicable to other versions with new MQP tool releases. To check if the patch is compatible with your Magento version, run ./vendor/bin/magento-patches status

Issue

The user is not being sent to the Magento order success page, so they refresh the blank page and the second order is placed, causing duplicate orders.

Steps to reproduce

Prerequisites

• Magento is installed.
• PayPal Express checkout payment is configured.
• Log in to Magento admin. Go to Stores > Configuration > Sales > Payment Methods > select Paypal Express Checkout > Configure > Advanced Settings > Skip Order Review Step > No.

1. Log in as a user.
2. Select an item and click Add to Cart.
3. Click on the cart and click Proceed to Checkout.
4. Proceed to the PayPal Express window and make a payment.
5. You are redirected to the Magento Order Review Page.
6. Press the Place Order button.
7. Emulate system error due to server infrastructure issues. The user will see a blank page.
8. Refresh the page.

Expected result: 

• The customer is redirected to the Order Review page and sees an error message "A successful payment transaction has already been completed. Please, check if the order has been placed."
• In the payment.log which is located in /var/log/payment.log there is an error 10415, but only one order was created.

Actual result:

• As the customer is not sent to the Magento order success page, they refresh the blank page, and a second order is placed, so two duplicated orders are created.
• In the payment.log which is located in /var/log/payment.log there is an error 10415.

Apply the patch

For instructions on how to apply an MQP patch, use the following links depending on your Magento product:

• Magento Commerce: DevDocs Apply patches using Magento Quality Patches Tool.
• Magento Commerce Cloud: DevDocs Upgrades and Patches > Apply patches.

Related reading

To learn more about Magento Quality Patches, refer to:

•  Magento Quality Patches released: a new tool to self-serve quality patches.
•  Check if patch is available for your Magento issue using Magento Quality Patches.

For info about other patches available in MQP tool, refer to the Patches available in MQP tool section.