This indicates an attack attempt against a Code Execution vulnerability in ZTE Routers.
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.
ZTE F460 modems
ZTE F660 modems
System Compromise: Remote attacker can gain control of vulnerable systems.
Currently we are unaware of any vendor supplied patch for this issue.