NetworkLoadBalancer with unencrypted Cassandra Client (TCP:9042) is potentially exposed to the public internet

Services and databases store data that may be sensitive, protected by law, subject to regulatory requirements or compliance standards. It is highly recommended that access to data will be restricted to encrypted protocols. This rule detects network settings that may expose data via unencrypted protocol over the public internet or to a too wide local scope.

Risk Level: High
Cloud Entity: Network Load Balancer
CloudGuard Rule ID: D9.AWS.NET.AG2.1.NetworkLoadBalancer.9042.TCP
Covered by Spectral: No
Category: Networking & Content Delivery


NetworkLoadBalancer where isPublic=true and nics contain [ subnet.routeTable.associations length()>0 ] and nics contain [ subnet.routeTable.routes contain [ destinationCidrBlock='' and gatewayId regexMatch /gw/ ] ] should not have inboundRules contain [ port<=9042  and portTo>=9042  and protocol in ('TCP', 'ALL') and scope isPublic() and scope numberOfHosts()>=32 ]


It is recommended to remove the rules that allow permissive SSH/Remote/Admin access.

If public interface exists, remove it and limit the access scope within the VPC only to applications or instances that requires access.

Amazon Reference:

As a further protection, use CloudGuard Dynamic Access Leasing to limit access to SSH/Remote Desktop only from allowed sources and only when needed.
For more information please refer to:

Network Load Balancer

A Network Load Balancer functions at the fourth layer of the Open Systems Interconnection (OSI) model. It can handle millions of requests per second. After the load balancer receives a connection request, it selects a target from the target group for the default rule. It attempts to open a TCP connection to the selected target on the port specified in the listener configuration.

Compliance Frameworks

  • BP-0318
  • CCMV301
  • GDPR
  • ISO27001
  • LGPD
  • NIST800534
  • PCIDSS32
  • SOC2