This indicates an attack attempt against an Information Disclosure vulnerability in Microsoft Internet Explorer.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted HTML. A remote attacker may be able to gain unauthorized access to sensitive information on the affected machines via a crafted HTML.
Windows Server 2008
Windows Server 2008 R2
Information Disclosure: Remote attackers can gain sensitive information from vulnerable systems
Apply the most recent upgrade or patch from the vendor.