Unspecified vulnerability in the "alignment check exception handling" in Ubuntu 5.10, 6.06 LTS, and 6.10 for the PowerPC (PPC) allows local users to cause a denial of service (kernel panic) via unspecified vectors.
http://www.us.debian.org/security/2006/dsa-1237
http://www.us.debian.org/security/2006/dsa-1233
http://www.ubuntu.com/usn/usn-395-1
http://www.securityfocus.com/bid/21523
http://www.novell.com/linux/security/advisories/2006_79_kernel.html
http://secunia.com/advisories/23474
http://secunia.com/advisories/23395
http://secunia.com/advisories/23384