RBAC Roles with Read Secrets Permissions

• Query id: 826abb30-3cd5-4e0b-a93b-67729b4f7e63
• Query name: RBAC Roles with Read Secrets Permissions
• Platform: Terraform
• Severity: Medium
• Category: Access Control
• URL: Github

Description

Roles and ClusterRoles with get/watch/list RBAC permissions on Kubernetes secrets are dangerous and should be avoided. In case of compromise, attackers could abuse these roles to access sensitive data, such as passwords, tokens and keys
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - tf file

resource "kubernetes_role" "example1" {
  metadata {
    name = "terraform-example1"
    labels = {
      test = "MyRole"
    }
  }

  rule {
    api_groups     = [""]
    resources      = ["secrets", "namespaces"]
    resource_names = ["foo"]
    verbs          = ["get", "list", "watch"]
  }
  rule {
    api_groups = ["apps"]
    resources  = ["deployments"]
    verbs      = ["get", "list"]
  }
}

resource "kubernetes_cluster_role" "example2" {
  metadata {
    name = "terraform-example2"
  }

  rule {
    api_groups = [""]
    resources  = ["namespaces", "secrets"]
    verbs      = ["get", "list", "watch"]
  }
  rule {
    api_groups = ["apps"]
    resources  = ["deployments"]
    verbs      = ["get", "list"]
  }
}


resource "kubernetes_role" "example3" {
  metadata {
    name = "terraform-example3"
    labels = {
      test = "MyRole"
    }
  }

  rule {
    api_groups     = [""]
    resources      = ["secrets", "namespaces"]
    resource_names = ["foo"]
    verbs          = ["get", "list", "watch"]
  }

}

resource "kubernetes_cluster_role" "example4" {
  metadata {
    name = "terraform-example4"
  }

  rule {
    api_groups = [""]
    resources  = ["namespaces", "secrets"]
    verbs      = ["get", "list", "watch"]
  }

}

Code samples without security vulnerabilities

Negative test num. 1 - tf file

resource "kubernetes_role" "example1" {
  metadata {
    name = "terraform-example1"
    labels = {
      test = "MyRole"
    }
  }

  rule {
    api_groups     = [""]
    resources      = ["pods"]
    resource_names = ["foo"]
    verbs          = ["get", "list", "watch"]
  }
  rule {
    api_groups = ["apps"]
    resources  = ["deployments"]
    verbs      = ["get", "list"]
  }
}

resource "kubernetes_cluster_role" "example2" {
  metadata {
    name = "terraform-example2"
  }

  rule {
    api_groups = [""]
    resources  = ["namespaces", "pods"]
    verbs      = ["get", "list", "watch"]
  }
}