This indicates an attack attempt against an Arbitrary File Upload vulnerability in WordPress Creative Contact Form Plugin.
The vulnerability is due to insufficient sanitizing of user supplied inputs when handling a crafted file upload. It allows a remote attacker to upload an arbitrary file onto vulnerable systems via a crafted file upload.
Creative Contact Form for WordPress 0.9.7 and prior
Creative Contact Form for Joomla extension 2.0.0 and prior
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.