MS13-051 Microsoft Office bulletin was release Tuesday 11th 2013 during the traditional Patch Tuesday. This bulletin fix one vulnerability, CVE-2013-1331, with a base CVSS score of 9.3 and targeting Microsoft Office 2003 and Office for Mac (2011). This vulnerability allow remote code execution and was reported by Andrew Lyons and Neel Mehta of Google Inc.
Microsoft has also release additional information’s and it appears that some “bad guys” were using this vulnerability as a zero-day in targeted attacks. The vulnerability is related on how Microsoft Office render malformed PNG files leading to a classic stack based buffer overflow.