This indicates an attack attempt to exploit a remote Code Execution vulnerability in Microsoft Windows.
The vulnerability is due to a flaw in the vulnerable system when handling a crafted .theme file. A remote attacker could exploit this to execute arbitrary code execution within the context of the application, via a crafted .theme file.
Microsoft Windows Vista
Microsoft Windows XP
Microsoft Windows Server 2003
Microsoft Windows Server 2008
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.