AWS Foundational Security Best Practice
ES.2
Elasticsearch domains should be in a VPC
Severity
Cloud Platforms
Resources
CRITICAL
AWS
Amazon Elasticsearch
This control checks whether Elasticsearch domains are in a VPC. It does not evaluate the VPC subnet routing configuration to determine public reachability. This AWS control also does not check whether the Amazon OpenSearch Service resource-based policy permits public access by other accounts or external entities. You should ensure that Elasticsearch domains are not attached to public subnets. See Resource-based policies (https://docs.aws.amazon.com/elasticsearch-service/latest/developerguide/es-ac.html#es-ac-types-resource) in the Amazon OpenSearch Service (successor to Amazon Elasticsearch Service) Developer Guide. You should also ensure that your VPC is configured according to the recommended best practices. See Security best practices for your VPC (https://docs.aws.amazon.com/vpc/latest/userguide/vpc-security-best-practices.html) in the Amazon VPC User Guide.