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# AWS Elasticsearch is not configured inside a VPC misconfiguration detected in code

## Rule Details

|                        |                                |
| ---------------------- | ------------------------------ |
| Cortex AppSec Rule ID  | APPSEC\_AWS\_137               |
| Category - Subcategory | Public Exposure - VPC VCN VNet |
| Provider               | AWS                            |
| Severity               | LOW                            |
| Framework              | Terraform, Terraform Plan      |

## Impact

AWS Elasticsearch domains that reside within a VPC have an extra layer of security when compared to ES domains that use public endpoints. Launching an Amazon ES cluster within an AWS VPC enables secure communication between the ES cluster (domain) and other AWS services without the need for an Internet Gateway, a NAT device or a VPN connection and all traffic remains secure within the AWS Cloud.

## How to Fix

*Resource:* aws\_elasticsearch\_domain

* *Arguments:* vpc\_options \[source,go]

***

resource "aws\_elasticsearch\_domain" "es" { domain\_name = var.domain elasticsearch\_version = "6.3"

cluster\_config { instance\_type = "m4.large.elasticsearch" }

* vpc\_options {
* subnet\_ids = \[
* data.aws\_subnet\_ids.selected.ids\[0],
* data.aws\_subnet\_ids.selected.ids\[1],
* ]

security\_group\_ids = \[aws\_security\_group.es.id] }

## }


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