TCP port 9300 is commonly used by Elasticsearch, which is an open-source distributed search and analytics engine. It allows unrestricted inbound access by default, which could lead to unauthorized access to sensitive data or even complete system compromise. Therefore, it is important to ensure that this port is not accessible from untrusted networks and only authorized users and applications have access to it.
Here are the steps to remediate the issue of unrestricted inbound access to TCP port 9300, which is used by ElasticSearch:
- Identify the security group(s) associated with the ElasticSearch cluster that allow unrestricted inbound access to port 9300.
- Update the inbound rules for the security group(s) associated with the ElasticSearch cluster to allow access only from trusted sources, such as specific IP addresses or other security groups that contain trusted instances.
- Verify that the updated inbound rules are effective by attempting to connect to the ElasticSearch cluster from an untrusted source. The connection attempt should fail.
- Monitor the security group(s) associated with the ElasticSearch cluster to ensure that the rules remain in place and that no new rules are added that allow unrestricted inbound access to port 9300.
- Consider implementing additional security measures, such as encryption and authentication, to further secure access to the ElasticSearch cluster.
Note: Remediation steps provided by Lightlytics are meant to be suggestions and guidelines only. It is crucial to thoroughly verify and test any remediation steps before applying them to production environments. Each organization's infrastructure and security needs may differ, and blindly applying suggested remediation steps without proper testing could potentially cause unforeseen issues or vulnerabilities. Therefore, it is strongly recommended that you validate and customize any remediation steps to meet your organization's specific requirements and ensure that they align with your security policies and best practices.