The Juniper multicast edge router must be configured to establish boundaries for administratively scoped multicast traffic.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-253987	JUEX-RT-000150	SV-253987r843994_rule		Low

Description
If multicast traffic is forwarded beyond the intended boundary, it is possible that it can be intercepted by unauthorized or unintended personnel. Administrative scoped multicast addresses are locally assigned and are to be used exclusively by the enterprise network or enclave. Administrative scoped multicast traffic must not cross the enclave perimeter in either direction. Restricting multicast traffic makes it more difficult for a malicious user to access sensitive traffic. Admin-Local scope is encouraged for any multicast traffic within a network intended for network management, as well as for control plane traffic that must reach beyond link-local destinations.

Description

If multicast traffic is forwarded beyond the intended boundary, it is possible that it can be intercepted by unauthorized or unintended personnel. Administrative scoped multicast addresses are locally assigned and are to be used exclusively by the enterprise network or enclave. Administrative scoped multicast traffic must not cross the enclave perimeter in either direction. Restricting multicast traffic makes it more difficult for a malicious user to access sensitive traffic. Admin-Local scope is encouraged for any multicast traffic within a network intended for network management, as well as for control plane traffic that must reach beyond link-local destinations.

STIG	Date
Juniper EX Series Switches Router Security Technical Implementation Guide	2024-06-10

Details

Check Text ( C-57439r843992_chk )
Review the router configuration and verify that admin-scope multicast traffic is blocked at the external edge. Verify either a scope is defined for specific interfaces or a scope policy is applied. [edit routing-options multicast] scope { prefix 239.0.0.0/8; interface [ ]; } scope { prefix ff08::/16; interface [ ]; } -or- [edit policy-options] policy-statement { term 1 { from { route-filter 239.0.0.0/8 orlonger; route-filter ff08::/16 orlonger; } then reject; } } [edit routing-options multicast] scope-policy If the router is not configured to establish boundaries for administratively scoped multicast traffic, this is a finding.

Check Text ( C-57439r843992_chk )

Review the router configuration and verify that admin-scope multicast traffic is blocked at the external edge.

Verify either a scope is defined for specific interfaces or a scope policy is applied.
[edit routing-options multicast]
scope {
prefix 239.0.0.0/8;
interface [ ];
}
scope {
prefix ff08::/16;
interface [ ];
}

-or-

[edit policy-options]
policy-statement {
term 1 {
from {
route-filter 239.0.0.0/8 orlonger;
route-filter ff08::/16 orlonger;
}
then reject;
}
}
[edit routing-options multicast]
scope-policy

If the router is not configured to establish boundaries for administratively scoped multicast traffic, this is a finding.

Fix Text (F-57390r843993_fix)
Configure the policy to deny packets with multicast administratively scoped destination addresses. set routing-options multicast scope prefix 239.0.0.0/8; set routing-options multicast scope prefix ff08::/16; -or- set policy-options policy-statement term 1 from route-filter 239.0.0.0/8 orlonger set policy-options policy-statement term 1 from route-filter ff08::/16 orlonger Apply the multicast boundary at the appropriate interfaces. set routing-options multicast scope interface [ ] set routing-options multicast scope interface [ ] -or- set routing-options multicast scope-policy

Fix Text (F-57390r843993_fix)

Configure the policy to deny packets with multicast administratively scoped destination addresses.
set routing-options multicast scope prefix 239.0.0.0/8;
set routing-options multicast scope prefix ff08::/16;

-or-

set policy-options policy-statement term 1 from route-filter 239.0.0.0/8 orlonger
set policy-options policy-statement term 1 from route-filter ff08::/16 orlonger

Apply the multicast boundary at the appropriate interfaces.
set routing-options multicast scope interface [ ]
set routing-options multicast scope interface [ ]

-or-

set routing-options multicast scope-policy