Heartbleed in Hanami with Dynamodb

Heartbleed (CVE-2014-0160) is a vulnerability in OpenSSL’s TLS heartbeat extension that allows an attacker to read memory from the server. While Hanami is a Ruby web framework and DynamoDB is a managed NoSQL database, the combination can expose sensitive data when Heartbleed compromises the runtime environment that hosts Hanami and its DynamoDB client connections.

In a typical Hanami application using the aws-sdk-dynamodb gem, the process memory may contain AWS credentials, session tokens, or application logic when communicating with DynamoDB. If the server runs an affected OpenSSL version and an attacker triggers a TLS heartbeat request, memory contents—potentially including DynamoDB client configuration, temporary security tokens, or query parameters—can be exfiltrated. This risk is elevated when Hanami services run on infrastructure that terminates TLS at the load balancer or application server without patching OpenSSL, and the application frequently interacts with DynamoDB, increasing the chance that sensitive data resides in memory at the time of exploitation.

An attacker leveraging Heartbleed against a Hanami service might capture serialized AWS request objects, IAM role credentials attached to the host (if using EC2 instance profiles), or fragments of DynamoDB table names and key attribute names. For example, a Hanami controller that constructs a GetItem request using inline key material could leak primary key values in memory. Because DynamoDB operations often include sensitive user identifiers or internal business keys, these fragments become high-value targets when combined with a memory disclosure bug like Heartbleed.

Notably, middleBrick’s unauthenticated scan can surface indicators such as outdated OpenSSL versions in the server stack and insecure handling of AWS credentials in runtime configurations. While middleBrick does not fix the vulnerability, its findings can guide teams to remediate the OpenSSL issue and reduce the exposure surface for Hanami services that interact with DynamoDB.

To reduce risk, remediate both the OpenSSL vulnerability and the way Hanami handles DynamoDB credentials and requests. Below are concrete steps and code examples tailored for a Hanami application using DynamoDB.

• Upgrade OpenSSL and runtime dependencies: Ensure the operating system and Ruby environment use an OpenSSL version that mitigates Heartbleed (OpenSSL 1.0.1g or later). Verify with openssl version.
• Use IAM roles instead of embedding credentials: On EC2 or ECS, assign an IAM role to the host and remove any hardcoded AWS secret keys from Hanami configuration files.
• Leverage short-lived credentials: If you must use explicit keys, rotate them frequently and avoid storing them in source control.
• Minimize sensitive data in memory: Avoid passing sensitive query parameters via logs or exception messages. Use structured logging that filters DynamoDB key attribute values.

Example Hanami controller using the AWS SDK for DynamoDB with secure practices:

require "aws-sdk-dynamodb"
require "hanami/controller"

# Configure the client outside the request cycle to reuse connections safely
DYNAMODB_CLIENT = Aws::DynamoDB::Client.new(
  region: ENV.fetch("AWS_REGION"),
  # Use default credential chain (IAM role, environment variables, or shared config)
  # Do NOT inline access_key_id or secret_access_key here
)

class ItemsController < Hanami::Controller
  def show
    table_name = ENV.fetch("DYNAMODB_ITEMS_TABLE")
    input = { key: params.fetch(:id) }
    # Validate and sanitize input to avoid injection or malformed requests
    key = { id: { s: input[:key] } }

    begin
      resp = DYNAMODB_CLIENT.get_item({
        table_name: table_name,
        key: key
      })
      item = resp.item
      # Avoid logging raw item values that may contain sensitive data
      logger.info("Fetched item with id=#{input[:key]}")
      @item = item ? Hash[item.map { |k, v| [k, v.to_s] }] : nil
    rescue Aws::DynamoDB::Errors::ServiceError => e
      logger.error("DynamoDB error: #{e.class} — #{e.message}")
      @item = nil
    end

    render "items/show"
  end
end

Example secure configuration for environment variables (do not commit to version control):

# .env.production
AWS_REGION=us-east-1
DYNAMODB_ITEMS_TABLE=prod_items
# Rely on IAM role for EC2/ECS; do not set AWS_ACCESS_KEY_ID or AWS_SECRET_ACCESS_KEY here

Example GitHub Action to fail builds if the OpenSSL version is outdated (add API security checks to your CI/CD pipeline):

- name: Check OpenSSL version
  run: |
    REQUIRED="1.0.1g"
    CURRENT=$(openssl version | cut -d' ' -f2)
    if [ "$(printf '%s\n' "$REQUIRED" "$CURRENT" | sort -V | head -n1)” != "$REQUIRED” ]; then
      echo "OpenSSL version $CURRENT is vulnerable to Heartbleed-like issues; upgrade to at least $REQUIRED"
      exit 1
    fi

By addressing the OpenSSL issue and following secure patterns for DynamoDB access in Hanami, you reduce the impact of memory disclosure bugs and limit the exposure of sensitive runtime data.