Security update MS09-017 addresses the PowerPoint (PPT) zero-day vulnerability

From MSRC Engineering :

Security update MS09-017 addresses the PowerPoint (PPT) zero-day vulnerability that has recently been used in targeted attacks. We issued security advisory 969136 with workarounds on April 2nd after we first saw the exploits in-the-wild abusing this vulnerability. We also published an SRD blog entry describing how to analyze exploits and an MMPC blog entry with more details about the exploits we had seen. Now the security update is ready for you to install. This update has a few differences compared to previous Office security updates that we’d like to make sure you understand.

Microsoft Security Bulletin MS09-017 - Critical