Cursor auth

CSRF Protection Accidentally Disabled by Cursor

After Cursor refactored your security middleware, CSRF tokens are no longer being validated. Form submissions succeed even with invalid tokens, creating a serious security vulnerability.

The CSRF middleware was either removed or incorrectly configured during code reorganization.

Error Messages You Might See

ForbiddenError: invalid csrf token CSRF token mismatch No CSRF token found
ForbiddenError: invalid csrf tokenCSRF token mismatchNo CSRF token found

Common Causes

  1. CSRF middleware commented out or removed during cleanup
  2. Exemption list too broad, accidentally exempting all routes
  3. Token name changed (csrf vs _csrf) without updating templates
  4. Session middleware moved after CSRF middleware in chain
  5. CSRF middleware configuration set to disabled mode

How to Fix It

Re-enable CSRF middleware: app.use(csrf({cookie: false, sessionKey: 'session'})). Verify token is passed in forms: <input type='hidden' name='_csrf' value='<%= csrfToken %>'>. Only exempt webhook endpoints like /stripe/webhook.

Real developers can help you.

MFox MFox Full-stack professional senior engineer (15+years). Extensive experience in software development, qa, and IP networking. Simon A. Simon A. I'm a backend developer building APIs, emulators, and interactive game systems. Professionally, I've developed Java/Spring reporting solutions, managed relational and NoSQL databases, and implemented CI/CD workflows. Matthew Butler Matthew Butler Systems Development Engineer @ Amazon Web Services Daniel Vázquez Daniel Vázquez Software Engineer with over 10 years of experience on Startups, Government, big tech industry & consulting. Prakash Prajapati Prakash Prajapati I’m a Senior Python Developer specializing in building secure, scalable, and highly available systems. I work primarily with Python, Django, FastAPI, Docker, PostgreSQL, and modern AI tooling such as PydanticAI, focusing on clean architecture, strong design principles, and reliable DevOps practices. I enjoy solving complex engineering problems and designing systems that are maintainable, resilient, and built to scale. Costea Adrian Costea Adrian Embedded Engineer specilizing in perception systems. Latest project was a adas camera calibration system. Matthew Jordan Matthew Jordan I've been working at a large software company named Kainos for 2 years, and mainly specialise in Platform Engineering. I regularly enjoy working on software products outside of work, and I'm a huge fan of game development using Unity. I personally enjoy Python & C# in my spare time, but I also specialise in multiple different platform-related technologies from my day job. Yovel Cohen Yovel Cohen I got a lot of experience in building Long-horizon AI Agents in production, Backend apps that scale to millions of users and frontend knowledge as well. Luca Liberati Luca Liberati I work on monoliths and microservices, backends and frontends, manage K8s clusters and love to design apps architecture Matt Butler Matt Butler Software Engineer @ AWS

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help

Frequently Asked Questions

How do I disable CSRF for specific routes?

Use middleware options or conditionally apply: app.post('/webhook', (req,res,next) => csrfProtection(req, res, next) || skip middleware).

Why is my AJAX failing with CSRF?

Pass token in X-CSRF-Token header. Fetch the token from the DOM: document.querySelector('meta[name=csrf-token]').content.

Related Cursor Issues

Can't fix it yourself?
Real developers can help.

You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.

Get Help