Cisco 12000 with IOS 12.0 and line cards based on Engine 2 and earlier allows remote attackers to cause a denial of service (CPU consumption) by flooding the router with traffic that generates a large number of ICMP Unreachable replies.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not block non-initial packet fragments, which allows remote attackers to bypass the ACL.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not handle the "fragment" keyword in a compiled ACL (Turbo ACL) for packets that are sent to the router, which allows remote attackers to cause a denial of service via a flood of fragments.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not properly handle the implicit "deny ip any any" rule in an outgoing ACL when the ACL contains exactly 448 entries, which can allow some outgoing packets to bypass access restrictions.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not support the "fragment" keyword in an outgoing ACL, which could allow fragmented packets in violation of the intended access.

Cisco 12000 with IOS 12.0 and lines card based on Engine 2 does not properly handle an outbound ACL when an input ACL is not configured on all the interfaces of a multi port line card, which could allow remote attackers to bypass the intended access controls.

Cisco 12000 with IOS 12.0 and line cards based on Engine 2 does not properly filter does not properly filter packet fragments even when the "fragment" keyword is used in an ACL, which allows remote attackers to bypass the intended access controls.