The Juniper perimeter router must be configured to drop IPv6 packets containing an extension header with the Endpoint Identification option.
An XCCDF Rule
Description
<VulnDiscussion>The optional and extensible natures of the IPv6 extension headers require higher scrutiny since many implementations do not always drop packets with headers that it cannot recognize, and hence could cause a Denial-of-Service on the target device. In addition, the type, length, value (TLV) formatting provides the ability for headers to be very large. This option type is associated with the Nimrod Routing system and has no defining RFC document.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-233297r855916_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Step 1: Configure a filter to block packets with either a Hop-by-Hop or Destination Option header as shown in the example.
user@R1# edit firewall family inet6
user@R1# edit filter IPV6-INGRESS-FILTER
user@R1# set term HOP_BY_HOP_HEADER from next-header hop-by-hop
user@R1# set term HOP_BY_HOP_HEADER then discard syslog