To instruct the firewall what to do with certain IP packets it receives in the zone, specify the following settings.
Zone Protection Profile Settings—Packet Based Attack Protection
Spoofed IP address
Packet Based Attack Protection
Discard packets with a spoofed IP address.
On internal zones only, drop spoofed IP address packets to ensure that on ingress, the source address matches the firewall routing table.
Strict IP Address Check
Discard packets with malformed source or destination IP addresses. For example, discard packets where the source or destination IP address is the same as the network interface address, is a broadcast address, a loopback address, a link-local address, an unspecified address, or is reserved for future use.
For a firewall in Common Criteria (CC) mode, you can enable logging for discarded packets. On the firewall web interface, select
. In the Manage Logs section, select
Selective Auditand enable
Packet Drop Logging.
Discard fragmented IP packets.
IP Option Drop
Select the settings in this group to enable the firewall to drop packets containing these IP Options.
Strict Source Routing
Discard packets with the Strict Source Routing IP option set. Strict Source Routing is an option whereby a source of a datagram provides routing information through which a gateway or host must send the datagram.
Drop packets with strict source routing because source routing allows adversaries to bypass Security policy rules that use the destination IP address as the matching criteria.
Loose Source Routing
Discard packets with the Loose Source Routing IP option set. Loose Source Routing is an option whereby a source of a datagram provides routing information and a gateway or host is allowed to choose any route of a number of intermediate gateways to get the datagram to the next address in the route.
Drop packets with loose source routing because source routing allows adversaries to bypass Security policy rules that use the destination IP address as the matching criteria.
Discard packets with the Timestamp IP option set.
Discard packets with the Record Route IP option set. When a datagram has this option, each router that routes the datagram adds its own IP address to the header, thus providing the path to the recipient.
Discard packets if the security option is defined.
Discard packets if the Stream ID option is defined.
Discard packets if the class and number are unknown.
Discard unknown packets.
Discard packets if they have incorrect combinations of class, number, and length based on RFCs 791, 1108, 1393, and 2113.
Discard malformed packets.