Lovable
security
XSS Vulnerability in Lovable App User Input
Your Lovable app displays user-submitted content (comments, profile names, form inputs) without properly sanitizing it. This allows attackers to inject malicious JavaScript that runs in other users' browsers.
Cross-site scripting (XSS) is a serious vulnerability that can steal user sessions, redirect users to phishing sites, or modify what your app displays. If your app has any feature where one user's input is shown to another user, it may be vulnerable.
The issue often goes unnoticed until someone submits a script tag in a form field and it executes, or until your app is flagged in a security scan.
Error Messages You Might See
Content Security Policy violation
Refused to execute inline script
Unsafe HTML content detected
Common Causes
- Using dangerouslySetInnerHTML — Lovable may generate React code that renders user content as raw HTML
- No input sanitization — User input is stored and displayed exactly as entered, including HTML and script tags
- Template literals in DOM — User data inserted into the page using template strings without escaping
- Missing Content-Security-Policy headers — No CSP headers to prevent inline script execution
How to Fix It
- Never use dangerouslySetInnerHTML with user data — Replace it with regular text rendering that auto-escapes HTML
- Install DOMPurify — If you must render HTML, use a sanitization library like DOMPurify to strip malicious content
- Add Content-Security-Policy headers — Configure CSP headers to prevent inline script execution
- Validate and sanitize on the server — Clean user input before storing it in the database, not just when displaying it
- Test with common XSS payloads — Try submitting <script>alert('xss')</script> in your form fields to verify they're safe
Real developers can help you.
Anthony Akpan
Developer with 8 years of experience building softwares fro startups
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Costea Adrian
Embedded Engineer specilizing in perception systems. Latest project was a adas camera calibration system.
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.
Sage Fulcher
Hey I'm Sage! Im a Boston area software engineer who grew up in South Florida. Ive worked at a ton of cool places like a telehealth kidney care startup that took part in a billion dollar merger (Cricket health/Interwell health), a boutique design agency where I got to work on a ton of exciting startups including a photography education app, a collegiate Esports league and more (Philosophie), a data analytics as a service startup in Cambridge (MA) as well as at Phillips and MIT Lincoln Lab where I designed and developed novel network security visualizations and analytics. I've been writing code and furiously devoted to using computers to make people’s lives easier for about 17 years. My degree is in making computers make pretty lights and sounds. Outside of work I love hip hop, the Celtics, professional wrestling, magic the gathering, photography, drumming, and guitars (both making and playing them)
Rudra Bhikadiya
I build and fix web apps across Next.js, Node.js, and DBs.
Comfortable jumping into messy code, broken APIs, and mysterious bugs.
If your project works in theory but not in reality, I help close that gap.
Antriksh Narang
5 years+ Experienced Dev (Specially in Web Development), can help in python, javascript, react, next.js and full stack web dev technologies.
Krishna Sai Kuncha
Experienced Professional Full stack Developer with 8+ years of experience across react, python, js, ts, golang and react-native. Developed inhouse websearch tooling for AI before websearch was solved : )
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.
Jacek Rozanski
Senior PHP/Symfony developer and DevOps engineer with 20+ years of professional experience, running opcode.pl (web development agency, est. 2004).
Day job: I'm the sole backend developer at merketing company where I own and maintain 11 PHP/Symfony microservices on AWS (ECS Fargate, RDS, S3, CloudFront), handle the full CI/CD pipeline (Bitbucket Pipelines, Docker), and manage monitoring with Sentry and CloudWatch. These services handle high request volumes in production every month.
What I bring to AI-built apps:
- I audit and fix security issues (OWASP methodology), performance bottlenecks, and architectural problems in codebases generated by Cursor, Claude Code, Lovable, Bolt, and v0
- I refactor AI-generated prototypes into production-grade applications with proper error handling, testing, and clean architecture (SOLID, DDD, hexagonal architecture)
- I set up the infrastructure AI tools don't touch: AWS hosting, CI/CD pipelines, automated deployments, database optimization, monitoring, and alerting
- I integrate external services: payment providers, email systems, partner APIs, SSO/auth
Tech stack: PHP 8.x, Symfony, React, Next.js, PostgreSQL, MySQL, Docker, AWS (ECS, RDS, S3, SQS/SNS, CloudFront), Terraform, Supabase. I also use AI tools daily (Claude Code, Cursor) in my own workflow, so I understand both the strengths and the gaps in AI-generated code.
Based in Poland (CET timezone). Available for async work and calls during EU/US business hours.
You don't need to be technical. Just describe what's wrong and a verified developer will handle the rest.
Get HelpFrequently Asked Questions
What is XSS and why is it dangerous?
Cross-site scripting (XSS) allows attackers to inject malicious scripts into your app. When other users visit the page, the script runs in their browser and can steal their login sessions, personal data, or redirect them to fake sites.
Can React prevent XSS automatically?
React escapes content by default when you use JSX expressions like {userInput}. However, using dangerouslySetInnerHTML or inserting content via DOM manipulation bypasses this protection.