STIGQter STIGQter: STIG Summary: Arista MLS EOS 4.X Router Security Technical Implementation Guide Version: 2 Release: 2 Benchmark Date: 02 Apr 2025:

The Arista perimeter router must be configured to filter ingress traffic at the external interface on an inbound direction.

DISA Rule

SV-256018r882396_rule

Vulnerability Number

V-256018

Group Title

SRG-NET-000205-RTR-000003

Rule Version

ARST-RT-000370

Severity

CAT II

CCI(s)

Weight

10

Fix Recommendation

This requirement is not applicable for the DODIN backbone.

Bind the ingress ACL to the external interface (inbound).

Step 1: Configure the ACL.

LEAF-1A(config)#ip access-list INBOUND
LEAF-1A(config-acl-INBOUND)#10 permit tcp 10.10.10.0/24 host 10.20.10.1 eq ssh telnet
LEAF-1A(config-acl-INBOUND)#20 permit ip 10.10.10.0/24 192.168.10.0/24
LEAF-1A(config-acl-INBOUND)#30 permit udp 10.20.20.0/24 any eq bootps snmp
LEAF-1A(config-acl-INBOUND)#40 deny ip any any log

Step 2: Apply the ACL inbound on all external interfaces.

LEAF-1A(config)#interface ethernet 13
LEAF-1A(config-if-Et13)#ip access-group INBOUND in

Check Contents

This requirement is not applicable for the DODIN backbone.

Review the Arista router configuration to verify the ingress ACL is bound to the external interface in an inbound direction.

Step 1: To verify the ingress ACL is bound to the external interface in an inbound direction, execute the command "sh ip access-list".

ip access-list INBOUND
10 permit tcp 10.10.10.0/24 host 10.20.10.1 eq ssh telnet
20 permit ip 10.10.10.0/24 192.168.10.0/24
30 permit udp 10.20.20.0/24 any eq bootps snmp

Step 2: To verify the ACL is applied inbound on all external interfaces, execute the command "sh run int Eth YY".

interface ethernet 13
ip access-group INBOUND in

If the Arista router is not configured to filter traffic entering the network at the external interface in an inbound direction, this is a finding.

Vulnerability Number

V-256018

Documentable

False

Rule Version

ARST-RT-000370

Severity Override Guidance

This requirement is not applicable for the DODIN backbone.

Review the Arista router configuration to verify the ingress ACL is bound to the external interface in an inbound direction.

Step 1: To verify the ingress ACL is bound to the external interface in an inbound direction, execute the command "sh ip access-list".

ip access-list INBOUND
10 permit tcp 10.10.10.0/24 host 10.20.10.1 eq ssh telnet
20 permit ip 10.10.10.0/24 192.168.10.0/24
30 permit udp 10.20.20.0/24 any eq bootps snmp

Step 2: To verify the ACL is applied inbound on all external interfaces, execute the command "sh run int Eth YY".

interface ethernet 13
ip access-group INBOUND in

If the Arista router is not configured to filter traffic entering the network at the external interface in an inbound direction, this is a finding.

Check Content Reference

M

Target Key

5513