This indicates an attack attempt to exploit a Code Execution vulnerability in Microsoft Internet Explorer.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted HTML file. An attacker can exploit this by tricking an unsuspecting user into visiting a malicious webpage and execute arbitrary code on vulnerable systems.
Internet Explorer 9
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.