Quote from: Adobe vulnerabilityAPSB06-08The file and folder permissions for Adobe Reader and Adobe Acrobat can permit non-privileged users to change key program files on Mac OSX. This condition presents a risk for shared, multi-user systems. Adobe Reader and Acrobat update 6.0.5 resolves this condition. Adobe recommends that customers using Adobe Reader or Adobe Acrobat apply these updates.
For full details and upgrade path see this link (http://www.adobe.com/support/security/bulletins/apsb06-08.html).