This indicates an attack attempt to exploit a remote Code Execution vulnerability in Microsoft Windows.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted RTF file. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted RTF file.
Windows Server 2008
Windows Server 2008 R2
Windows Server 2012 R2
Windows RT 8.1
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.