Mobile Accounts in Apple Mac OS X before 10.7.5 and 10.8.x before 10.8.2 saves password hashes for external-account use even if external accounts are not enabled, which might allow remote attackers to determine passwords via unspecified access to a mobile account.
http://support.apple.com/kb/HT5501
http://lists.apple.com/archives/security-announce/2012/Sep/msg00004.html