The Nokia perimeter router must be configured to drop IPv6 packets containing a Hop-by-Hop or Destination Option extension header with an undefined option type.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-283845 | NOKI-RT-000270 | SV-283845r1203784_rule | CCI-002403 | medium |
| Description | ||||
| The optional and extensible natures of the IPv6 extension headers require higher scrutiny because many implementations do not always drop packets with headers that cannot be recognized, which 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. | ||||
| STIG | Date | |||
| Nokia Service Router OS 25.x Router Security Technical Implementation Guide | 2026-06-15 | |||
Details
Check Text (C-283845r1203784_chk)
This requirement is not applicable for the DODIN Backbone.
Review the router configuration and determine if filters are bound to the applicable interfaces to drop all inbound IPv6 packets containing an undefined option type value regardless of whether they appear in a Hop-by-Hop or Destination Option header. Undefined values are 0x02, 0x03, 0x06, 0x9 - 0xE, 0x10 - 0x22, 0x24, 0x25, 0x27 - 0x2F, and 0x31 - 0xFF.
Verify the IPv6 filter has the HopByHop option set to "True", as shown in the example below:
- show filter ipv6 40
Entry : 10 (Inactive)
Description : (Not Specified)
Log Id : n/a
Src. IP : ::/0
Src. Port : n/a
Dest. IP : ::/0
Dest. Port : n/a
Next Header : Undefined
Dscp : Undefined
ICMP Type : Undefined ICMP Code : Undefined
Sampling : Off Int. Sampling : On
Tcp-flag : (Not Specified)
Fragment : Off
HopByHop Opt : True Routing Type0 : Off
Verify an "Ing IPv6 Flt" has been applied to the interface, as shown in the example below:
- show router interface "TO-PE2" detail | match "Ingr IPv6 Flt"
Egr IPv6 Flt : none Ingr IPv6 Flt : 40
If the router is not configured to drop IPv6 packets containing a Hop-by-Hop or Destination Option extension header with an undefined option type, this is a finding.
Fix Text (F-88315r1203783_fix)
Configure the router to drop all inbound IPv6 packets containing an undefined option type value regardless of whether they appear in a Hop-by-Hop or Destination Option header.
Configure the IPv6 filter, as shown in the example below:
Note: This will drop all Hop-by-Hop Option headers.
- configure filter ipv6-filter 40 create
- config>filter>ipv6-filter# default-action forward
- config>filter>ipv6-filter# entry 10 create
- config>filter>ipv6-filter>entry$ match hop-by-hop-opt true
- config>filter>ipv6-filter>entry$ action drop
- config>filter>ipv6-filter>entry$ exit all
Apply the IPv6 filter to the interface:
- configure router interface "TO-PE2" ingress filter ipv6 40