A few weeks ago, Microsoft posted security advisory 2953095 for a Word RTF Memory Corruption Vulnerability (CVE-2014-1761). To exploit the vulnerability, an attacker would need to specially craft an RTF file and use social engineering techniques to trick a user into previewing or opening the malicious file. There have been reports of attacks in the wild taking advantage of this vulnerability targeting Microsoft Word 2010 installations. It's a real nasty vulnerability that affects a wide range of Microsoft products and there are many attack vectors.