This indicates an attack attempt against a memory-corruption vulnerability in Microsoft Office.
The vulnerability is caused by an error when the vulnerable software handles Office files with embedded malfromed Office Art drawing records. It may allow remote attackers to execute arbitrary code by sending a crafted Office file.
Microsoft Office XP Service Pack 3
Microsoft Office 2003 Service Pack 3
Microsoft Office 2007 Service Pack 2
Microsoft Office 2010 (32-bit editions)
Microsoft Office 2010 (64-bit editions)
Microsoft Office 2004 for Mac
Microsoft Office 2008 for Mac
Open XML File Format Converter for Mac
System Compromise: Remote attackers can gain control of vulnerable systems.
Refer to the vendor's web site for the suggested workaround: