Shopware is an open source commerce platform based on Symfony Framework and Vue js. The newsletter double opt-in validation was not checked properly, and it was possible to skip the complete double opt in process. As a result operators may have inconsistencies in their newsletter systems. This problem has been fixed with version 6.4.18.1. Users are advised to upgrade. Users unable to upgrade may find security measures are available via a plugin for major versions 6.1, 6.2, and 6.3. Users may also disable newsletter registration completely.

Shopware has Improper Input Validation issue in newsletter subscription