Title

The Juniper perimeter router must be configured to block all packets with any IP options. (Cat II impact)

Discussion

Packets with IP options are not fast switched and henceforth must be punted to the router processor. Hackers who initiate denial-of-service (DoS) attacks on routers commonly send large streams of packets with IP options. Dropping the packets with IP options reduces the load of IP options packets on the router. The end result is a reduction in the effects of the DoS attack on the router and on downstream routers.

Check Content

This requirement is not applicable for the DoDIN Backbone. Review the router configuration to determine if it will block all packets with IP options. firewall { family inet { filter INBOUND_FILTER { term DROP_IPOPTIONS { from { ip-options any; } then { syslog; discard; } } term BLOCK_BOGONS { from { source-prefix-list { BOGON_PREFIXES; } } then { syslog; discard; } } term ALLOW_ABC { … … … term DENY_ALL_OTHER { then { log; syslog; reject; } } } If the router is not configured to drop all packets with IP options, this is a finding.

Fix Text

This requirement is not applicable for the DoDIN Backbone. Configure the router to drop all packets with IP options. [edit firewall family inet filter INBOUND_FILTER] set term DROP_IPOPTIONS from ip-options any set term DROP_IPOPTIONS then discard insert term DROP_IPOPTIONS before term BLOCK_BOGONS

Additional Identifiers

Rule ID: SV-217040r604135_rule

Vulnerability ID: V-217040

Group Title: SRG-NET-000205-RTR-000015

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.