Cross Site Request Forgery in Sinatra with Cockroachdb

Cross Site Request Forgery (CSRF) in a Sinatra app that uses CockroachDB arises when an application relies solely on cookies for session identity and does not enforce anti-CSRF tokens for state-changing requests. Because CockroachDB is a distributed SQL database often used in production web services, Sinatra routes that perform mutations (POST, PUT, DELETE) directly against CockroachDB can inadvertently enable replay or unauthorized actions if a victim’s browser is tricked into submitting authenticated requests.

Consider a Sinatra route that transfers funds by updating rows in a CockroachDB table via an HTTP POST without any CSRF protection:

post '/transfer' do
  user_id = session[:user_id]
  amount = params[:amount]
  target = params[:target]
  DB["UPDATE accounts SET balance = balance - ? WHERE id = ?", amount, user_id].execute
  DB["UPDATE accounts SET balance = balance + ? WHERE id = ?", amount, target].execute
  "Transfer submitted"
end

If the application does not validate an origin or include a per-request token, an attacker can craft a malicious page that causes the victim’s browser to send the same request with the victim’s credentials. CockroachDB’s transactional guarantees do not prevent this; the database executes whatever SQL the application sends. The risk is compounded when sessions are stored in cookies without the SameSite attribute or when the app exposes unsafe GET endpoints that mutate data, violating idempotency expectations and increasing the CSRF surface.

Because middleBrick scans unauthenticated attack surfaces and checks for Authentication issues and BOLA/IDOR patterns, it can surface endpoints that lack anti-CSRF controls while noting that findings do not include automatic remediation. The scanner evaluates headers, cookie attributes, and observable behavior, mapping results to OWASP API Top 10 and related compliance frameworks.

To mitigate CSRF in Sinatra with CockroachDB, implement anti-CSRF tokens and enforce strict SameSite and Secure cookie attributes. Use a per-form or per-session token validated on each state-changing request, and ensure your routes distinguish read from write operations.

Example: Secure form with per-request token

# Sinatra app setup
require 'sinatra'
require 'securerandom'
require 'base64'

helpers do
  def csrf_token
    session[:csrf_token] ||= SecureRandom.base64(32)
  end

  def verify_csrf(token)
    return false if token.nil?
    Rack::Utils.secure_compare(token, session[:csrf_token])
  end
end

# Set secure cookie (in a production deployment, use HTTPS)
before do
  response.set_cookie 'session_id', {
    value: session.id,
    httponly: true,
    secure: true,
    samesite: 'Lax'
  }
end

Example: POST route with token validation and CockroachDB transaction

post '/transfer' do
  halt 403, 'Invalid CSRF token' unless verify_csrf(params[:csrf_token])

  user_id = session[:user_id]
  amount = params[:amount].to_i
  target = params[:target]

  DB.transaction do
    DB["UPDATE accounts SET balance = balance - ? WHERE id = ?", amount, user_id].execute
    DB["UPDATE accounts SET balance = balance + ? WHERE id = ?", amount, target].execute
  end

  "Transfer completed"
end

Example: Safe GET endpoints and idempotent design

Avoid using GET for mutations. If you must provide operations that change state, use POST with CSRF protection:

# Prefer explicit POST rather than GET for mutations
get '/account/:id' do
  user_id = session[:user_id]
  account = DB[:accounts].where(id: user_id).first
  account.to_json
end

post '/account/:id/freeze' do
  halt 403, 'Invalid CSRF token' unless verify_csrf(params[:csrf_token])
  DB[:accounts].where(id: params[:id]).update(frozen: true)
  "Account frozen"
end

Checklist for Sinatra + CockroachDB

• Use per-form or per-session anti-CSRF tokens for all state-changing POST/PUT/DELETE requests.
• Set SameSite=Lax or SameSite=Strict on session cookies; mark cookies as Secure in production.
• Ensure idempotent operations and avoid GET endpoints that execute mutations.
• Validate the Origin header where appropriate for additional defense in depth.

middleBrick can help identify endpoints missing these protections by scanning your API and providing prioritized findings with remediation guidance. If you want to track security posture over time, the Dashboard and Pro plan continuous monitoring let you configure scans and receive alerts when risk scores change.