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Hello @indykoning,

Thank you for the report and collaboration!

Could you elaborate the issue and also let us know the impact of the issue, steps to reproduce and use case.

In our specific usecase a project wanted randomised order increment ids.
As a safeguard we check if this increment id already exists in the database using the following snippet

/** @var \Magento\Sales\Api\Data\OrderInterface $this->order */
$this->order->loadByIncrementId($incrementId)->getEntityId() === null

(Note us purposefully not catching NoSuchEntityException as the function is designed to always return an order. Either an existing one, or a new one)

Which calls $this->order->loadByAttribute('increment_id', $incrementId) and eventually calls the load function.

Since a completely empty Order model is returned (which it should), the Authorisation check referenced in the PR fails because it tries to check a customer id which does not exist.

• For guests this isn't an issue since they have no customer id and the security check is not triggered
• For customers this means their order cannot be placed because we didn't catch the exception

By checking wether the Order exists in the first place before doing the security check we prevent this exception.

Hello @indykoning,

Thank you for the detailed explanation.

Looks like you are returning a empty order, due to which isAllowed method is returning false because this empty order does not have a CustomerId. This can be considered as a feature request because this happens only when the order is empty.
Hence markig it the same.

Thank you.