Internet-Security.com TCP port 9307 details

Elasticsearch: its inter-node transport protocol listens on TCP 9300 by default and auto-increments to 9301–9399 when needed; thus 9307 is commonly used by an Elasticsearch node’s transport layer on multi-node hosts or when lower ports are taken.
OpenSearch (the Elasticsearch fork) uses the same transport mechanism and port range, so OpenSearch nodes may listen on TCP 9307 for cluster transport.
Managed offerings such as Elastic Cloud and Amazon OpenSearch Service use this 9300–9399 transport range internally for node-to-node communication, which can include 9307, though it’s typically not exposed publicly.

TCP 9307