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 deny network traffic by default and allow network traffic by exception.

DISA Rule

SV-256015r882387_rule

Vulnerability Number

V-256015

Group Title

SRG-NET-000202-RTR-000001

Rule Version

ARST-RT-000330

Severity

CAT I

CCI(s)

• CCI-001109 - Deny network communications traffic by default and allow network communications traffic by exception at managed interfaces; and/or for organization-defined systems.

Weight

10

Fix Recommendation

This requirement is not applicable for the DODIN backbone.

Configure the Arista perimeter router to deny network traffic by default and allow network traffic by exception.

Step 1: Configure an ACL inbound to allow traffic per the requirement and deny all by default.

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

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

router(config)#interface ethernet 13
router(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 access control list (ACL) or filter is configured to allow specific ports and protocols and deny all other traffic.

The filter must be configured inbound on all external interfaces.

Step 1: Verify the ACL is configured to allow traffic per the requirement and deny all by default. 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 tcp 10.10.10.0/24 any eq www https
30 permit udp 10.20.20.0/24 any eq bootps snmp

Step 2: 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 ACL or filter is not configured to allow specific ports and protocols and deny all other traffic, this is a finding.

If the filter is not configured inbound on all external interfaces, this is a finding.

Vulnerability Number

V-256015

Documentable

False

Rule Version

ARST-RT-000330

Severity Override Guidance

This requirement is not applicable for the DODIN backbone.

Review the Arista router configuration to verify the access control list (ACL) or filter is configured to allow specific ports and protocols and deny all other traffic.

The filter must be configured inbound on all external interfaces.

Step 1: Verify the ACL is configured to allow traffic per the requirement and deny all by default. 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 tcp 10.10.10.0/24 any eq www https
30 permit udp 10.20.20.0/24 any eq bootps snmp

Step 2: 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 ACL or filter is not configured to allow specific ports and protocols and deny all other traffic, this is a finding.

If the filter is not configured inbound on all external interfaces, this is a finding.

Check Content Reference

M

Target Key

5513