drools <=7.59.x is affected by an XML External Entity (XXE) vulnerability in KieModuleMarshaller.java. The Validator class is not used correctly, resulting in the XXE injection vulnerability.
An XXE flaw was found in the jBPM runtime while executing BPMN2 files. A remote attacker could use this flaw to read files accessible to the user running the application server, and potentially perform other more advanced XXE attacks.