This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening.
This signature detects attempts to arbitrary code execution in activex WBEMSingleView.ocx of WMI Administrative Tools.
WMI Administrative Tools is prone to a vulnerability that lets attackers execute arbitrary code.WBEMSingleView.ocx has a method AddContextRef,which could directly call the address give as parameters.
Successfully exploiting these issues will allow attackers to execute arbitrary within the context of the application (typically Internet Explorer) that uses the ActiveX control.