Magento versions 2.3.4 and earlier, 2.2.11 and earlier (see note), 1.14.4.4 and earlier, and 1.9.4.4 and earlier have a security mitigation bypass vulnerability. Successful exploitation could lead to arbitrary code execution.
https://github.com/advisories/GHSA-gffx-9f36-r8wp
https://helpx.adobe.com/security/products/magento/apsb20-22.html