GrandNode Voucher ConfirmOrder race condition

A vulnerability was detected in GrandNode up to 2.3.0. The impacted element is an unknown function of the file /checkout/ConfirmOrder/ of the component Voucher Handler. The manipulation of the argument giftvouchercouponcode results in race condition. The attack may be launched remotely. The attack requires a high level of complexity. The exploitability is regarded as difficult. The vendor was contacted early about this disclosure but did not respond in any way.