Fix.

Website and web app security testing

Identify vulnerabilities before malicious actors exploit them. We run comprehensive security audits and penetration tests on modern web applications and SaaS backends.

Modern web applications combine complex client-side state, third-party authentication providers, cloud databases, and microservices. A single misconfigured policy can expose your entire customer database to public visitors.

We perform rigorous security testing on your web application, simulating real attack vectors to uncover permission leaks, exposed administrative secrets, and broken access controls.

Sound familiar?

  • You are preparing for public launch or investor diligence and need independent verification that user data is protected.
  • Your application uses Supabase, Firebase, or GraphQL, and you are not certain every table enforces strict Row-Level Security.
  • Client bundles contain multiple API keys and you need confirmation that administrative credentials remain private.
  • Users have reported seeing account details belonging to other tenants.
  • You need a clear remediation roadmap that your developers can implement without slowing product velocity.

What we test

  • Database Row-Level Security bypasses: We inspect every public table and view to ensure unauthorized visitors cannot query records directly through API clients.
  • Broken object-level authorization (BOLA): We test whether authenticated users can access, modify, or delete resources belonging to other organizations by changing URL parameters or request payloads.
  • Client bundle credential leaks: We audit production JavaScript assets for leaked administrative keys, including Supabase service role keys, Stripe secret keys, and third-party API tokens.
  • Authentication and session security: We test session invalidation, JWT token expiry, password reset flows, and privilege escalation vulnerabilities.
  • Payment and webhook validation: We verify that payment webhooks enforce cryptographic signatures and cannot be replayed to grant free subscription tiers.

What you receive

  1. Executive summary: A clear risk summary designed for founders, leadership teams, and prospective investors.
  2. Technical vulnerability catalog: Every finding documented with reproduction steps, severity rating (Critical, High, Medium, Low), and affected endpoints.
  3. Exact code fixes: Ready-to-apply SQL policies, backend code snippets, and environment variable configurations to resolve each vulnerability immediately.
  4. Verification re-test: Once your team applies the fixes, we re-test each resolved issue to confirm the vulnerability is closed.

Questions

Do you require full access to our source code?

We offer both black-box testing (evaluating only your live application URL as an external attacker would) and white-box testing (reviewing both repository code and live endpoints). White-box testing provides the most comprehensive security verification.

Will security testing disrupt our active users?

No. Security testing is conducted against staging environments or isolated test accounts with strict rate limits to prevent production service disruption.

What clients said

Copied word for word from completed orders on Fiverr, typos and all.

First engagement and I am impressed. Slick, fast, professional and insightful.
revnuu_ioUnited KingdomDeployments & DevOpsVerified Fiverr order
two words. simply awesome. everything that was built was 1st class and communicating was simple and consistent. can't fault the work and the level of service. I was so excited to get the final App.. way better than I could have hoped for!!
nvsmediagroupUnited KingdomTroubleshooting & ImprovementsVerified Fiverr order
Amazing work, and I can assure you this was prob his most complex project ever. His attention to detail, willingness to figure things out, but also taking a proactive stance and not only come to you with any bigs or issues, he came with suggestions with real solutions. Amazing work
jerred_questUnited StatesDevelopment & MVPVerified Fiverr order

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Whether you are building a new SaaS platform from scratch, launching a mobile product, designing a high-conversion interface, or need an urgent rescue for an AI-built app, we are ready to help. You will receive a clear scoped plan and milestone timeline within 1 to 2 business days.

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