Incomplete blacklist vulnerability in Launch Services in Apple Mac OS X 10.5.8 allows user-assisted remote attackers to execute arbitrary code via a .fileloc file, which does not trigger a "potentially unsafe" warning message in the Quarantine feature.
https://exchange.xforce.ibmcloud.com/vulnerabilities/53171
http://www.securityfocus.com/bid/36360
http://support.apple.com/kb/HT3865
http://secunia.com/advisories/36701
http://lists.apple.com/archives/security-announce/2009/Sep/msg00004.html