Cisco IOS 12.0 through 12.4 on Cisco 10000, uBR10012 and uBR7200 series devices handles external UDP packets that are sent to 127.0.0.0/8 addresses intended for IPC communication within the device, which allows remote attackers to cause a denial of service (device or linecard reload) via crafted UDP packets, a different vulnerability than CVE-2008-3806.