This indicates an attack attempt to exploit a remote Code Execution vulnerability in Avaya Communication Manager that was disclosed by Shadow Broker as EPICHERO exploit.
The vulnerability is due to insufficient sanitizing of user supplied inputs in the application. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application.
Avaya Communication Manager version S8710-013-00.0.340.3
System Compromise: Remote attackers can gain control of vulnerable systems
Currently we are unaware of any vendor supplied patch or updates available for this issue.