beecue FastBee SIP Message ReqAbstractHandler.java getRootElement xml external entity reference

A vulnerability was detected in beecue FastBee up to 2.1. Impacted is the function getRootElement of the file springboot/fastbee-server/sip-server/src/main/java/com/fastbee/sip/handler/req/ReqAbstractHandler.java of the component SIP Message Handler. The manipulation results in xml external entity reference. It is possible to launch the attack remotely. A high complexity level is associated with this attack. The exploitability is considered difficult. The project owner replied to the issue report: "Okay, we'll handle it as soon as possible."