Microsoft has released updates to Office 2008 and 2011, which include bug fixes and patches for security issues. The Office 2008 update include a fix for two PowerPoint vulnerabilities:
The vulnerabilities could allow remote code execution if a user opens a specially crafted PowerPoint file. An attacker who successfully exploited either of the vulnerabilities could take complete control of an affected system. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
And the Office 2011 update fixes a similar vulnerability in Word.