Adobe released Adobe Reader 9.3.1 which addresses a critical security vulnerability. Please see Security Bulletin APSB10-07 for details. Adobe always recommends that you install the latest security updates. For more information, see the Release Notes.  

The 9.3.1 update comes as a Windows Installer Patch file (MSP) for Adobe Reader 9.3. Check out "Deploy Adobe Acrobat and Reader" and the new 'Adobe Customization Wizard 9' which makes it very easy to customize the Adobe Reader for deployment: