syscall in the Linux kernel 2.6.8.1 and 2.6.10 for the AMD64 platform, when running in 32-bit compatibility mode, allows local users to cause a denial of service (kernel hang) via crafted arguments.
http://www.securityfocus.com/bid/13904
http://www.novell.com/linux/security/advisories/2005_29_kernel.html