Service With External Load Balancer

• Query id: 2a52567c-abb8-4651-a038-52fa27c77aed
• Query name: Service With External Load Balancer
• Platform: Terraform
• Severity: Medium
• Category: Networking and Firewall
• URL: Github

Description

Service has an external load balancer, which may cause accessibility from other networks and the Internet
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - tf file

resource "kubernetes_service" "example1" {
  metadata {
    name = "terraform-example1"
    annotations = {
      "service.beta.kubernetes.io/aws-load-balancer-internal" = "false"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

resource "kubernetes_service" "example2" {
  metadata {
    name = "terraform-example2"
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

Positive test num. 2 - tf file

resource "kubernetes_service" "example2" {
  metadata {
    name = "terraform-example2"
    annotations = {
      "service.beta.kubernetes.io/azure-load-balancer-internal" = "false"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

resource "kubernetes_service" "example3" {
  metadata {
    name = "terraform-example3"
    annotations = {
      "networking.gke.io/load-balancer-type" = "External"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

resource "kubernetes_service" "example4" {
  metadata {
    name = "terraform-example4"
    annotations = {
      "cloud.google.com/load-balancer-type" = "External"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

Code samples without security vulnerabilities

Negative test num. 1 - tf file

resource "kubernetes_service" "example3" {
  metadata {
    name = "terraform-example3"
    annotations = {
      "service.beta.kubernetes.io/aws-load-balancer-internal" = "true"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

Negative test num. 2 - tf file

resource "kubernetes_service" "example2" {
  metadata {
    name = "terraform-example2"
    annotations = {
      "service.beta.kubernetes.io/azure-load-balancer-internal" = "true"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

resource "kubernetes_service" "example3" {
  metadata {
    name = "terraform-example3"
    annotations = {
      "networking.gke.io/load-balancer-type" = "Internal"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}

resource "kubernetes_service" "example4" {
  metadata {
    name = "terraform-example4"
    annotations = {
      "cloud.google.com/load-balancer-type" = "Internal"
    }
  }
  spec {
    selector = {
      app = kubernetes_pod.example.metadata.0.labels.app
    }
    session_affinity = "ClientIP"
    port {
      port        = 8080
      target_port = 80
    }

    type = "LoadBalancer"
  }
}