Traffic from the managed network will leak into the management network via the gateway router interface connected to the OOBM backbone.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17818	NET0988	SV-19304r1_rule		Medium

Description
If the gateway router is not a dedicated device for the OOBM network, several safeguards must be implemented for containment of management and production traffic boundaries such as using interface ACLs or filters at the boundaries between the two networks.

STIG	Date
Perimeter Router Security Technical Implementation Guide Juniper	2018-02-27

Details

Check Text ( C-20205r1_chk )
Examine the egress filter on the OOBM interface of the gateway router to verify that only traffic sourced from the management address space is allowed to transit the OOBM backbone. In the example configurations below, the 10.1.1.0/24 is the management network address space at the enclave or managed network and 10.2.2.0/24 is the management network address space at the NOC. interfaces { fe-0/0/0 { description “link to our Private Net” unit 0 { family inet { address 172.20.4.2/24; } } } fe-0/0/1 { description “link to our Service Net” unit 0 { family inet { address 172.20.5.2/24; } } } t3-3/0/3 { description “link to OOBM Backbone” unit 0 { family inet { filter { output OOBM-egress-filter; } address 10.1.20.3/24; } } } } firewall { filter OOBM-egress-filter { term allow-mgmt { from { source-address { 10.1.1.0/24; } destination-address { 10.2.2.0/24; } } then { accept; } } … … … term default-action { then { syslog; discard; } } } }

Check Text ( C-20205r1_chk )

Examine the egress filter on the OOBM interface of the gateway router to verify that only traffic sourced from the management address space is allowed to transit the OOBM backbone. In the example configurations below, the 10.1.1.0/24 is the management network address space at the enclave or managed network and 10.2.2.0/24 is the management network address space at the NOC.

interfaces {
fe-0/0/0 {
description “link to our Private Net”
unit 0 {
family inet {
address 172.20.4.2/24;
}
}
}
fe-0/0/1 {
description “link to our Service Net”
unit 0 {
family inet {
address 172.20.5.2/24;
}
}
}
t3-3/0/3 {
description “link to OOBM Backbone”
unit 0 {
family inet {
filter {
output OOBM-egress-filter;
}
address 10.1.20.3/24;
}
}
}
}
firewall {
filter OOBM-egress-filter {
term allow-mgmt {
from {
source-address {
10.1.1.0/24;
}
destination-address {
10.2.2.0/24;
}
}
then {
accept;
}
}
…
…
…
term default-action {
then {
syslog;
discard;
}
}
}
}

Fix Text (F-17733r1_fix)
Configure the OOBM gateway router interface ACLs to ensure traffic from the managed network does not leak into the management network.