This indicates an attack attempt to exploit an Unrestricted File Upload vulnerability in ShopNx.
A remote, unauthenticated attacker can exploit this vulnerability by uploading a malicious file to the targeted server. Successful exploitation would lead to execution of arbitrary code in the security context of SYSTEM or root on the server.
ShopNx released before 2017-11-17
System Compromise: Remote attackers can gain control of vulnerable systems.
Currently we are unaware of any vendor supplied patch for this issue.