This indicates an attack attempt against an Integer Overflow vulnerability in TeeChart Professional ActiveX Control.
The vulnerability, which is located in multiple TeeChart ActiveX control, can be exploited through misuse of a vulnerable method "AddSeries". An attacker can exploit this by tricking an unsuspecting user into visiting a malicious webpage and execute arbitrary code within the context of the application.
TeeChart5.ocx Version 188.8.131.52
TeeChart6.ocx Version 184.108.40.206
TeeChart7.ocx Version 220.127.116.11
TeeChart8.ocx Version 18.104.22.168
TeeChart2010.ocx Version 2010.0.0.3
System Compromise: Remote attackers can gain control of vulnerable systems.
Currently we are unaware of any vendor supplied patch or updates available for this issue.
Disable this ActiveX Control by setting its kill bit, by the method shown on the website: http://support.microsoft.com/kb/240797