DesktopServices in Apple Mac OS X 10.6 before 10.6.3 does not properly resolve pathnames in certain circumstances involving an application's save panel, which allows user-assisted remote attackers to trigger unintended remote file copying via a crafted share name.
http://support.apple.com/kb/HT4077
http://lists.apple.com/archives/security-announce/2010//Mar/msg00001.html