Api Key Exposure in Hanami with Dynamodb

In Hanami applications that interact with AWS Dynamodb, api key exposure typically arises when access keys are handled as runtime configuration rather than being injected securely at deployment. Hanami’s default project layout may store configuration in plain Ruby files or environment-loading code where sensitive values are accidentally committed to version control or logged. When combined with Dynamodb, which requires explicit credential signing for each request, any leaked access key grants an attacker direct control over database operations. Because Dynamodb requests are signed client-side, the key must be present in the Hanami app’s runtime environment; if exposed through logs, error pages, or debug endpoints, the attacker can enumerate tables, read or overwrite items, and bypass intended authorization boundaries.

During an unauthenticated scan with middleBrick, endpoints that expose configuration or debug information are tested for data exposure. If a Hanami endpoint returns stack traces containing Dynamodb access key identifiers or reveals metadata that suggests hardcoded credentials, middleBrick flags this as Data Exposure with high severity. The scan checks whether API responses contain patterns associated with leaked keys (e.g., strings matching AWS access key format) and whether error handling inadvertently surfaces internal configuration. Because Hanami apps often integrate Dynamodb through SDK clients, misconfigured clients that log request details can amplify exposure risk, especially when combined with missing encryption in transit protections or weak runtime isolation.

Remediation guidance centers on credential isolation and strict error handling. Hanami apps should avoid embedding Dynamodb access keys in source code or initializer files that may be checked into repositories. Instead, use environment variables injected by the runtime platform, and ensure that Hanami’s configuration layer does not log raw parameters or responses. middleBrick’s findings map to OWASP API Top 10 A01:2023 Broken Object Level Authorization and A05:2021 Security Misconfiguration, as leaked keys can enable privilege escalation across tenant data. By rotating exposed keys immediately and applying least-privilege IAM policies scoped to specific Dynamodb tables and operations, you reduce the blast radius of any accidental disclosure.

To securely integrate Dynamodb with Hanami, move all credentials out of the application codebase and into secure runtime injection. Hanami’s configuration system allows environment-based settings that are not persisted in files that might be committed. Use AWS SDK for Ruby with explicit credential providers that reference environment variables or instance profiles, avoiding static access keys in Hanami initializers.

Example of a secure Hanami initializer that references environment variables and avoids logging sensitive data:

require 'aws-sdk-dynamodb'

module MyApp
  class Database
    def self.client
      @client ||= Aws::DynamoDB::Client.new(
        region: ENV.fetch('AWS_REGION', 'us-east-1'),
        access_key_id: ENV.fetch('AWS_ACCESS_KEY_ID', nil),
        secret_access_key: ENV.fetch('AWS_SECRET_ACCESS_KEY', nil),
        session_token: ENV.fetch('AWS_SESSION_TOKEN', nil)
      )
    end
  end
end

Ensure that the Hanami app never logs request parameters or responses that might contain key material. Configure the SDK to suppress debug logging in production:

Aws.config.update({logger: nil, log_level: :warn})

When deploying to environments that support IAM roles (e.g., EC2 instance profiles or ECS task roles), omit access_key_id and secret_access_key entirely to rely on the instance metadata service:

client = Aws::DynamoDB::Client.new(region: 'us-east-1')

Apply table-level permissions using IAM policies that follow least privilege. For example, if a Hanami service only needs to read user profiles from a table named UserProfiles, scope the policy to GetItem and Query actions on that specific table ARN. This prevents compromised keys from being used to perform destructive operations across your DynamoDB instance.

middleBrick’s Pro plan supports continuous monitoring and CI/CD integration, allowing you to automatically fail builds if a scan detects exposed credentials or insecure Dynamodb configurations in your Hanami codebase. By integrating the GitHub Action, you can enforce security gates before deployment, ensuring that any new configuration adhering to secure patterns is validated against the scanner’s checks.