This indicates an attack attempt to exploit a Remote Code Execution vulnerability in D-Link DWR series Router.
The vulnerability is due to the software's failure to adequately check user-supplied data in HTTP requests. Remote attackers may exploit this to execute arbitrary code.
D-Link DWR-116 Firmware V.1.06 and priors
D-Link DWR-512 Firmware V.2.02 and priors
D-Link DWR-712 Firmware V.2.02 and priors
D-Link DWR-912 Firmware V.2.02 and priors
D-Link DWR-921 Firmware V.2.02 and priors
D-Link DWR-111 Firmware V.1.01 and priors
System Compromise: Remote attackers can gain control of vulnerable systems.
Currently we are not aware of any vendor supplied patch for this issue