This indicates a potential XML External Entity attack.
XXE (XML eXternal Entity) attack is a form of attack where applications that parse XML inputs fail to properly validate the inputs. An attacker may be able to exploit this on a vulnerable system to execute arbitrary code within the context of the application or gain unauthorized access to sensitive information.
All web application environments that support XML are susceptible to this attack.
Remote attackers can execute arbitrary code or gain sensitive information.
Sanitize user inputs if possible or contact the vendor of the software for a solution or workaround.