Linux kernel 2.6 on Itanium (ia64) architectures allows local users to cause a denial of service via a "missing Itanium syscall table entry."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11039
https://euvd.enisa.europa.eu/vulnerability/EUVD-2005-0138