Apple Mac OS X 10.4.5 and allows local users to cause a denial of service (crash) via an undocumented system call.
https://exchange.xforce.ibmcloud.com/vulnerabilities/24682
http://www.vupen.com/english/advisories/2006/0597
http://www.securityfocus.com/bid/16654
http://securitytracker.com/id?1015634
http://secunia.com/advisories/18907
http://lists.apple.com/archives/security-announce/2006/Feb/msg00000.html