Clear-text protocols such as ftp, telnet or non-secure http lack encryption of transported data, as well as the capability to build an authenticated connection. It means that an attacker able to sniff traffic from the network can read, modify or corrupt the transported content. These protocols are not secure as they expose applications to an extensive range of risks:

Even in the context of isolated networks like offline environments or segmented cloud environments, the insider threat exists. Thus, attacks involving communications being sniffed or tampered with can still happen.

For example, attackers could successfully compromise prior security layers by:

In such cases, encrypting communications would decrease the chances of attackers to successfully leak data or steal credentials from other network components. By layering various security practices (segmentation and encryption, for example), the application will follow the defense-in-depth principle.

Note that using the http protocol is being deprecated by major web browsers.

In the past, it has led to the following vulnerabilities:

Ask Yourself Whether

There is a risk if you answered yes to any of those questions.

Recommended Secure Coding Practices

It is recommended to secure all transport channels (even local network) as it can take a single non secure connection to compromise an entire application or system.

Sensitive Code Example

For AWS Kinesis Data Streams server-side encryption:

resource "aws_kinesis_stream" "sensitive_stream" {
    encryption_type = "NONE" # Sensitive
}

For Amazon ElastiCache:

resource "aws_elasticache_replication_group" "example" {
    replication_group_id = "example"
    replication_group_description = "example"
    transit_encryption_enabled = false  # Sensitive
}

For Amazon ECS:

resource "aws_ecs_task_definition" "ecs_task" {
  family = "service"
  container_definitions = file("task-definition.json")

  volume {
    name = "storage"
    efs_volume_configuration {
      file_system_id = aws_efs_file_system.fs.id
      transit_encryption = "DISABLED"  # Sensitive
    }
  }
}

For Amazon OpenSearch domains:

resource "aws_elasticsearch_domain" "example" {
  domain_name = "example"
  domain_endpoint_options {
    enforce_https = false # Sensitive
  }
  node_to_node_encryption {
    enabled = false # Sensitive
  }
}

For Amazon MSK communications between clients and brokers:

resource "aws_msk_cluster" "sensitive_data_cluster" {
    encryption_info {
        encryption_in_transit {
            client_broker = "TLS_PLAINTEXT" # Sensitive
            in_cluster = false # Sensitive
        }
    }
}

For AWS Load Balancer Listeners:

resource "aws_lb_listener" "front_load_balancer" {
  protocol = "HTTP" # Sensitive

  default_action {
    type = "redirect"

    redirect {
      protocol = "HTTP"
    }
  }
}

HTTP protocol is used for GCP Region Backend Services:

resource "google_compute_region_backend_service" "example" {
  name                            = "example-service"
  region                          = "us-central1"
  health_checks                   = [google_compute_region_health_check.region.id]
  connection_draining_timeout_sec = 10
  session_affinity                = "CLIENT_IP"
  load_balancing_scheme           = "EXTERNAL"
  protocol                        = "HTTP" # Sensitive
}

Compliant Solution

For AWS Kinesis Data Streams server-side encryption:

resource "aws_kinesis_stream" "compliant_stream" {
    encryption_type = "KMS"
}

For Amazon ElastiCache:

resource "aws_elasticache_replication_group" "example" {
    replication_group_id = "example"
    replication_group_description = "example"
    transit_encryption_enabled = true
}

For Amazon ECS:

resource "aws_ecs_task_definition" "ecs_task" {
  family = "service"
  container_definitions = file("task-definition.json")

  volume {
    name = "storage"
    efs_volume_configuration {
      file_system_id = aws_efs_file_system.fs.id
      transit_encryption = "ENABLED"
    }
  }
}

For Amazon OpenSearch domains:

resource "aws_elasticsearch_domain" "example" {
  domain_name = "example"
  domain_endpoint_options {
    enforce_https = true
  }
  node_to_node_encryption {
    enabled = true
  }
}

For Amazon MSK communications between clients and brokers, data in transit is encrypted by default, allowing you to omit writing the encryption_in_transit configuration. However, if you need to configure it explicitly, this configuration is compliant:

resource "aws_msk_cluster" "sensitive_data_cluster" {
    encryption_info {
        encryption_in_transit {
            client_broker = "TLS"
            in_cluster = true
        }
    }
}

For AWS Load Balancer Listeners:

resource "aws_lb_listener" "front_load_balancer" {
  protocol = "HTTP"

  default_action {
    type = "redirect"

    redirect {
      protocol = "HTTPS"
    }
  }
}

HTTPS protocol is used for GCP Region Backend Services:

resource "google_compute_region_backend_service" "example" {
  name                            = "example-service"
  region                          = "us-central1"
  health_checks                   = [google_compute_region_health_check.region.id]
  connection_draining_timeout_sec = 10
  session_affinity                = "CLIENT_IP"
  load_balancing_scheme           = "EXTERNAL"
  protocol                        = "HTTPS"
}

Exceptions

No issue is reported for the following cases because they are not considered sensitive:

See