Missing Authentication in Buffalo with Cockroachdb

A Buffalo application using Cockroachdb can expose a Missing Authentication vulnerability when routes that interact with the database do not enforce authentication checks. Buffalo, by default, does not add authentication to handlers; it is the developer’s responsibility to ensure that sensitive endpoints are protected. If a route that queries or mutates data in Cockroachdb is left unprotected, an unauthenticated attacker can send direct HTTP requests to invoke those handlers.

Because Cockroachdb is a distributed SQL database, connection strings or environment-based configuration are typically used to establish database access. If a Buffalo handler connects to Cockroachdb without verifying the requester’s identity, the handler may execute privileged SQL statements (e.g., SELECT, UPDATE, DELETE) on sensitive tables such as users, permissions, or financial records. This becomes a classic Broken Object Level Authorization (BOLA) / Insecure Direct Object Reference (IDOR) pattern when the handler uses user-supplied input (like an :id parameter) to construct queries without confirming that the requesting user has the right to access that specific object.

In a black-box scan, middleBrick tests this attack surface by sending requests to endpoints that interact with Cockroachdb without credentials. For example, a handler mapped to GET /accounts/:account_id that opens a Cockroachdb connection and runs a query like SELECT * FROM accounts WHERE id = $1 will be invoked if the route lacks middleware or before actions that validate a session or token. Because no authentication guard exists, the scan can retrieve account data or trigger unauthorized operations, resulting in a high-severity finding mapped to OWASP API Top 10 A01: Broken Access Control and relevant compliance frameworks such as PCI-DSS and SOC2.

Additionally, the combination increases risk when developers rely on ambient database credentials stored in environment variables. If an endpoint is exposed, an attacker does not need to compromise the database directly; they can achieve data exposure or privilege escalation purely through the unprotected Buffalo routes. middleBrick’s checks for Authentication, BOLA/IDOR, and Data Exposure validate whether unauthenticated requests reach the database layer, highlighting routes that require remediation.

To remediate Missing Authentication in a Buffalo application using Cockroachdb, enforce authentication and authorization before any database operation. Use session-based or token-based verification, and ensure that object-level ownership checks are performed for each request. Below are concrete code examples that demonstrate secure patterns.

1. Require authentication via a before action

Define a plug that validates a session or JWT and assign current_user. Apply it to controllers that interact with Cockroachdb.

defmodule MyAppWeb.Plugs.RequireAuth do
  import Plug.Conn
  import Phoenix.Controller, only: [put_flash: 3, redirect: 2]

  def init(opts), do: opts

  def call(conn, _opts) do
    case conn.assigns[:current_user] do
      nil ->
        conn
        |> put_flash(:error, "You must be signed in")
        |> redirect(to: "/sessions/new")
        |> halt()
      _user -> conn
    end
  end
end

2. Authorize access to specific resources

In your controller, load the resource and verify ownership or role-based permissions before executing Cockroachdb queries.

defmodule MyAppWeb.AccountController do
  use MyAppWeb, :controller
  alias MyApp.Accounts
  alias MyApp.Repo

  plug :require_auth when action in [:show, :update, :delete]

  def show(conn, %{"id" => id}) do
    # Fetch the record from Cockroachdb
    account = Repo.one!(from a in "accounts", where: a.id == ^id)

    # Ensure the requesting user can access this account
    if Accounts.authorizable?(conn.assigns.current_user, account) do
      render(conn, "show.json", account: account)
    else
      conn
      |> put_status(:forbidden)
      |> json(%{error: "Forbidden"})
      |> halt()
    end
  end
end

3. Parameterized queries to prevent injection and enforce scoping

Always use Ecto queries or parameterized SQL to avoid injection and to keep scoping explicit. Combine scoping with authorization so users only see their own data.

defmodule MyApp.Accounts do
  import Ecto.Query
  alias MyApp.Repo
  alias MyApp.Accounts.UserAccount

  def list_user_accounts(user) do
    query = from ua in UserAccount,
            join: a in "accounts", on: ua.account_id == a.id,
            where: ua.user_id == ^user.id
    Repo.all(query)
  end

  def user_can_access?(user, account_id) do
    query = from ua in UserAccount,
            where: ua.user_id == ^user.id and ua.account_id == ^account_id
    Repo.exists?(query)
  end
end

4. Secure connection and configuration for Cockroachdb

Ensure your database connection uses strong credentials and TLS. In config, avoid exposing sensitive defaults and prefer runtime secrets.

import Config

config :my_app, MyApp.Repo,
  url: System.get_env("COCKROACH_URL"),
  ssl: [verify: :verify_peer, cacertfile: System.get_env("SSL_CERT_PATH")],
  parameters: [application_name: "buffalo_app"]

5. Integrate with Buffalo pipelines

Apply plugs in the router to protect groups of routes that perform Cockroachdb operations.

defmodule MyAppWeb.Router do
  use MyAppWeb, :router
  import MyAppWeb.Plugs.RequireAuth

  pipeline :api do
    plug :accepts, ["json"]
    plug RequireAuth
  end

  scope "/api", MyAppWeb do
    pipe_through :api

    get "/accounts/:id", AccountController, :show
    patch "/accounts/:id", AccountController, :update
    delete "/accounts/:id", AccountController, :delete
  end
end

By combining these patterns—authentication plugs, ownership checks, parameterized queries, and secure Cockroachdb configuration—you reduce the risk of Missing Authentication and related BOLA/IDOR issues. middleBrick can validate these controls by scanning endpoints to confirm that authentication and authorization are enforced before database interactions.