Traffic from the managed network is able to access the OOBM gateway router

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-17817	NET0987	SV-19302r2_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. It is imperative that hosts from the managed network are not able to access the OOBM gateway router.

STIG	Date
Infrastructure Router Security Technical Implementation Guide Juniper	2018-11-27

Details

Check Text ( C-20203r1_chk )
Review the ACL or filters for the router’s receive path and verify that only traffic sourced from the management network is allowed to access the router. This would include both management and control plane traffic. Step 1: Verify that an inbound filter has been applied to loopback interface. This filter is used to restrict all traffic to the router engine. The interface configuration should look similar to the following: interfaces { lo0 { unit 0 { family inet { no-redirects; filter { input router-protect-filter; } address 10.1.3.41/32; } } } } Note: the address block used for loopback addresses should be independent of the address space used for the management backbone, the NOC, or the local management subnet. Loopback address should be configured with /32 prefixes to enable proper route advertisements and optimum path reachability for both control plane and management plane traffic within the global management network. Step 2: Determine the address block of the management network at the NOC. In the example configuration below, the 10.2.2.0/24 is the management network at the NOC. Step 3: Verify that the ACL referenced by the ip receive acl statement restricts all management plane traffic to the validated network management address block at the NOC. Management traffic can include telnet, SSH, SNMP, TACACS, RADIUS, TFTP, TFTP, FTP, and ICMP. Control plane traffic from OOBM backbone neighbors should also be allowed to access the router. The filter configuration should look similar to the following: firewall { filter router-protect-filter { term ospf-neighbors { from { source-address { 10.2.2.0/24; } protocol ospf; } then { syslog; accept; } } term ssh-access { from { source-address { 10.2.2.0/24; } protocol tcp; destination-port ssh; } then { syslog; accept; } } term snmp-access { from { source-address { 10.2.2.24/32; 10.2.2.25/32; } protocol udp; destination-port snmp; } then { syslog; accept; } } term tacacs-access { from { source-address { 10.2.2.30/32; } protocol tcp; port tacacs-ds; } then { syslog; accept; } } term ftp-access { from { source-address { 10.2.2.77/32; } protocol tcp; port [ftp ftp-data]; } then { syslog; accept; } } term allow-ICMP { from { source-address { 10.2.2.0/24; } protocol icmp; } then accept; } term default-action { then { syslog; discard; } } } }

Check Text ( C-20203r1_chk )

Review the ACL or filters for the router’s receive path and verify that only traffic sourced from the management network is allowed to access the router. This would include both management and control plane traffic.

Step 1: Verify that an inbound filter has been applied to loopback interface. This filter is used to restrict all traffic to the router engine. The interface configuration should look similar to the following:
interfaces {
lo0 {
unit 0 {
family inet {
no-redirects;
filter {
input router-protect-filter;
}
address 10.1.3.41/32;
}
}
}
}

Note: the address block used for loopback addresses should be independent of the address space used for the management backbone, the NOC, or the local management subnet. Loopback address should be configured with /32 prefixes to enable proper route advertisements and optimum path reachability for both control plane and management plane traffic within the global management network.

Step 2: Determine the address block of the management network at the NOC. In the example configuration below, the 10.2.2.0/24 is the management network at the NOC.

Step 3: Verify that the ACL referenced by the ip receive acl statement restricts all management plane traffic to the validated network management address block at the NOC. Management traffic can include telnet, SSH, SNMP, TACACS, RADIUS, TFTP, TFTP, FTP, and ICMP. Control plane traffic from OOBM backbone neighbors should also be allowed to access the router. The filter configuration should look similar to the following:

firewall {
filter router-protect-filter {
term ospf-neighbors {
from {
source-address {
10.2.2.0/24;
}
protocol ospf;
}
then {
syslog;
accept;
}
}
term ssh-access {
from {
source-address {
10.2.2.0/24;
}
protocol tcp;
destination-port ssh;
}
then {
syslog;
accept;
}
}
term snmp-access {
from {
source-address {
10.2.2.24/32;
10.2.2.25/32;
}
protocol udp;
destination-port snmp;
}
then {
syslog;
accept;
}
}
term tacacs-access {
from {
source-address {
10.2.2.30/32;
}
protocol tcp;
port tacacs-ds;
}
then {
syslog;
accept;
}
}
term ftp-access {
from {
source-address {
10.2.2.77/32;
}
protocol tcp;
port [ftp ftp-data];
}
then {
syslog;
accept;
}
}
term allow-ICMP {
from {
source-address {
10.2.2.0/24;
}
protocol icmp;
}
then accept;
}
term default-action {
then {
syslog;
discard;
}
}
}
}

Fix Text (F-17732r1_fix)
Ensure that traffic from the managed network is not able to access the OOBM gateway router using either receive path or interface ingress ACLs.