RDS DB Instance Publicly Accessible

• Query id: 35113e6f-2c6b-414d-beec-7a9482d3b2d1
• Query name: RDS DB Instance Publicly Accessible
• Platform: Terraform
• Severity: Critical
• Category: Insecure Configurations
• CWE: 668
• URL: Github

Description

RDS must not be defined with public interface, which means the field 'publicly_accessible' should not be set to 'true' (default is 'false').
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - tf file

resource "aws_db_instance" "positive1" {
  allocated_storage    = 20
  storage_type         = "gp2"
  engine               = "mysql"
  engine_version       = "5.7"
  instance_class       = "db.t2.micro"
  name                 = "mydb"
  username             = "foo"
  password             = "foobarbaz"
  publicly_accessible = true
}

Positive test num. 2 - tf file

module "db" {
  source  = "terraform-aws-modules/rds/aws"
  version = "~> 3.0"

  identifier = "demodb"

  engine            = "mysql"
  engine_version    = "5.7.19"
  instance_class    = "db.t2.large"
  allocated_storage = 5
  publicly_accessible = true

  name     = "demodb"
  username = "user"
  password = "YourPwdShouldBeLongAndSecure!"
  port     = "3306"

  iam_database_authentication_enabled = true

  vpc_security_group_ids = ["sg-12345678"]

  maintenance_window = "Mon:00:00-Mon:03:00"
  backup_window      = "03:00-06:00"

  # Enhanced Monitoring - see example for details on how to create the role
  # by yourself, in case you don't want to create it automatically
  monitoring_interval = "30"
  monitoring_role_name = "MyRDSMonitoringRole"
  create_monitoring_role = true

  tags = {
    Owner       = "user"
    Environment = "dev"
  }

  # DB subnet group
  subnet_ids = ["subnet-12345678", "subnet-87654321"]

  # DB parameter group
  family = "mysql5.7"

  # DB option group
  major_engine_version = "5.7"

  # Database Deletion Protection
  deletion_protection = true

  parameters = [
    {
      name = "character_set_client"
      value = "utf8mb4"
    },
    {
      name = "character_set_server"
      value = "utf8mb4"
    }
  ]

  options = [
    {
      option_name = "MARIADB_AUDIT_PLUGIN"

      option_settings = [
        {
          name  = "SERVER_AUDIT_EVENTS"
          value = "CONNECT"
        },
        {
          name  = "SERVER_AUDIT_FILE_ROTATIONS"
          value = "37"
        },
      ]
    },
  ]
}

Code samples without security vulnerabilities

Negative test num. 1 - tf file

resource "aws_db_instance" "negative1" {
  allocated_storage    = 20
  storage_type         = "gp2"
  engine               = "mysql"
  engine_version       = "5.7"
  instance_class       = "db.t2.micro"
  name                 = "mydb"
  username             = "foo"
  password             = "foobarbaz"
  publicly_accessible = false
}

Negative test num. 2 - tf file

module "db" {
  source  = "terraform-aws-modules/rds/aws"
  version = "~> 3.0"

  identifier = "demodb"

  engine            = "mysql"
  engine_version    = "5.7.19"
  instance_class    = "db.t2.large"
  allocated_storage = 5
  publicly_accessible = false

  name     = "demodb"
  username = "user"
  password = "YourPwdShouldBeLongAndSecure!"
  port     = "3306"

  iam_database_authentication_enabled = true

  vpc_security_group_ids = ["sg-12345678"]

  maintenance_window = "Mon:00:00-Mon:03:00"
  backup_window      = "03:00-06:00"

  # Enhanced Monitoring - see example for details on how to create the role
  # by yourself, in case you don't want to create it automatically
  monitoring_interval = "30"
  monitoring_role_name = "MyRDSMonitoringRole"
  create_monitoring_role = true

  tags = {
    Owner       = "user"
    Environment = "dev"
  }

  # DB subnet group
  subnet_ids = ["subnet-12345678", "subnet-87654321"]

  # DB parameter group
  family = "mysql5.7"

  # DB option group
  major_engine_version = "5.7"

  # Database Deletion Protection
  deletion_protection = true

  parameters = [
    {
      name = "character_set_client"
      value = "utf8mb4"
    },
    {
      name = "character_set_server"
      value = "utf8mb4"
    }
  ]

  options = [
    {
      option_name = "MARIADB_AUDIT_PLUGIN"

      option_settings = [
        {
          name  = "SERVER_AUDIT_EVENTS"
          value = "CONNECT"
        },
        {
          name  = "SERVER_AUDIT_FILE_ROTATIONS"
          value = "37"
        },
      ]
    },
  ]
}