The Application Firewall in Apple Mac OS X 10.5 does not prevent a root process from accepting incoming connections, even when "Block incoming connections" has been set for its associated executable, which might allow remote attackers or local root processes to bypass intended access restrictions.
https://exchange.xforce.ibmcloud.com/vulnerabilities/38479
http://www.vupen.com/english/advisories/2007/3897
http://www.securityfocus.com/bid/26460
http://securitytracker.com/id?1018958
http://secunia.com/advisories/27695
http://lists.apple.com/archives/security-announce/2007/Nov/msg00004.html