Buffer overflow in kextload in Apple OS X, as used by TDIXSupport in Roxio Toast Titanium and possibly other products, allows local users to execute arbitrary code via a long extension argument.
http://www.securityfocus.com/bid/20034
http://www.netragard.com/pdfs/research/apple-kext-tools-20060822.txt
http://lists.grok.org.uk/pipermail/full-disclosure/2006-September/049452.html