Server-side Template Injection (SSTI) in Shopware 6 (<= v6.4.20.0, v6.5.0.0-rc1 <= v6.5.0.0-rc4), affecting both shopware/core and shopware/platform GitHub repositories, allows remote attackers with access to a Twig environment without the Sandbox extension to bypass the validation checks in `Shopware\Core\Framework\Adapter\Twig\SecurityExtension` and call any arbitrary PHP function and thus execute arbitrary code/commands via usage of fully-qualified names, supplied as array of strings, when referencing callables. Users are advised to upgrade to v6.4.20.1 to resolve this issue. This is a bypass of CVE-2023-22731.