Improper isolation or compartmentalization vulnerability in Apache Syncope. An administrator with adequate entitlements can import arbitrary BPMN process definitions via the REST API and then start the process. When a BPMN process containing a JUEL expression is imported and started, the expression is executed directly on the server, with no sandbox. This issue affects Apache Syncope: from 3.0.0-M0 through 3.0.16, from 4.0.0-M0 through 4.0.8, from 4.1.0 through 4.1.3. Users are recommended to upgrade to version 4.0.9 / 4.1.4, which fix this issue by rejecting BPMN definitions including expression attributes.