STIGQter: STIG Summary: Cisco IOS Router RTR Security Technical Implementation Guide Version: 2 Release: 1 Benchmark Date: 23 Oct 2020:

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

DISA Rule

SV-216624r531085_rule

Vulnerability Number

V-216624

Group Title

SRG-NET-000019-RTR-000005

Rule Version

CISC-RT-000810

Severity

CAT III

CCI(s)

CCI-001414 - The information system enforces approved authorizations for controlling the flow of information between interconnected systems based on organization-defined information flow control policies.

Weight

Fix Recommendation

Step 1: Configure the ACL to deny packets with multicast administratively scoped destination addresses as shown in the example below.

R2(config)#ip access-list standard MULTICAST_SCOPE
R2(config-std-nacl)#deny 239.0.0.0 0.255.255.255
R2(config-std-nacl)#permit any
R2(config-std-nacl)#exit

Step 2: Apply the multicast boundary at the appropriate interfaces as shown in the example below.

R2(config)#int g1/2
R2(config-if)#ip multicast boundary MULTICAST_SCOPE
R2(config-if)#end

Check Contents

Review the router configuration and verify that admin-scope multicast traffic is blocked at the external edge as shown in the example below.

interface GigabitEthernet1/2
ip address x.1.12.2 255.255.255.252
ip pim sparse-mode
ip multicast boundary MULTICAST_SCOPE
…
…
…
ip access-list standard MULTICAST_SCOPE
deny 239.0.0.0 0.255.255.255
permit any

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

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

DISA Rule

Vulnerability Number

Group Title

Rule Version

Severity

CCI(s)

Weight

Fix Recommendation

Check Contents

Vulnerability Number

Documentable

Rule Version

Severity Override Guidance

Check Content Reference

Target Key

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