Impact

It is possible to put the same line item multiple one in the cart using API, the Cart Validators checked the line item's individuality and the user was able to skip the clearance sale in cart

Patches

The problem has been fixed with 6.4.18.1

Workarounds

For older versions of 6.1, 6.2, and 6.3, corresponding security measures are also available via a plugin. For the full range of functions, we recommend updating to the latest Shopware version. Or disable the newsletter registration completely.

References

https://docs.shopware.com/en/shopware-6-en/security-updates/security-update-01-2023?category=security-updates