Free Website Vulnerability Scanner

Enter any URL and get an instant A+ to F security grade. No account needed for the quick check — register free to unlock 40+ parallel scan engines, SARIF/PDF reports, and CI/CD webhooks.

Scan your website free

What is a website vulnerability scanner?

A website vulnerability scanner is an automated tool that inspects your web application for security weaknesses before an attacker finds them. Vuln0x turns that inspection into a one-click workflow: paste a URL, hit scan, and within seconds you receive an A+ to F security grade alongside a prioritised list of findings. The free passive check covers the most critical surface-level signals — HTTP security headers, TLS certificate health, cookie attributes, and information disclosure. Register for a free account to unlock the full engine and scan website for vulnerability across 40+ categories in parallel, all without installing a single binary.

Unlike traditional enterprise scanners that were built for quarterly pen-test cycles, Vuln0x is designed for the pace of modern development. AI-assisted coding tools can ship a production app in hours — Vuln0x can check that app in seconds. Every scan produces a single numeric risk score so you, your team, and your stakeholders can understand the security posture at a glance without reading fifty pages of technical output.

How the scanner works

The website vulnerability check runs in two stages. The first stage is a passive surface check that requires no authentication and completes in under ten seconds. It sends the same HTTP requests a browser or search-engine crawler would make, then analyses the response headers, TLS handshake, redirect chains, cookie flags, and server banners. This stage is what drives the instant security grade you see above the fold — and it is completely free with no account required.

The second stage is the full deep scan, available after a free registration. This stage runs 40+ specialised scanner engines in parallel: header-policy analysers, SSL/TLS graders, JavaScript secret detectors, CORS misconfiguration probes, clickjacking testers, open-redirect fuzzers, SSRF endpoint checkers, and framework-specific modules for Next.js, React, WordPress, and more. Results arrive as a unified report with severity ratings, remediation guidance, and export options in SARIF (for GitHub Security), CSV, and PDF formats. The entire deep scan typically completes in under 60 seconds.

What the online vulnerability scan detects

A website vulnerability test with Vuln0x covers a broad surface area:

  • HTTP security headers — Content-Security-Policy, Strict-Transport-Security, X-Frame-Options, Referrer-Policy, Permissions-Policy, and X-Content-Type-Options. Missing or misconfigured headers are among the most common findings in 2026 security audits.
  • SSL/TLS configuration — expired certificates, weak cipher suites, TLS 1.0/1.1 support, mixed-content issues, and HSTS preload eligibility.
  • Cross-Origin Resource Sharing (CORS) — wildcard origins, missing Vary headers, and credentials-with-wildcard misconfigurations that allow cross-site data theft.
  • Cookie security — flags such as HttpOnly, Secure, and SameSite that prevent session hijacking and cross-site request forgery.
  • Cross-Site Scripting (XSS) — reflected and DOM-based injection points detected through safe probe payloads.
  • SQL injection — error-based and time-based probes against query parameters and form fields.
  • Server-Side Request Forgery (SSRF) — API routes and webhook endpoints that could be abused to reach internal services.
  • Exposed files and directories — source maps,.env leaks, backup files, admin panels, and directory listing.
  • Log4Shell (Log4j) — JNDI injection probes for systems still running vulnerable Log4j versions.
  • Clickjacking — frame-injection risks and missing frame-ancestor directives.
  • WordPress-specific CVEs — plugin, theme, and core version checks against the WPScan vulnerability database.

Free scan vs full scan — what is the difference?

The free passive scan gives you an instant security grade and a shortlist of the most impactful surface-level findings. It is the fastest way to get a website vulnerability check without any setup — no account, no credit card, no waiting. Useful for a quick sanity-check before a product launch or investor demo.

The full scan requires a free Vuln0x account, which comes with 50 credits on signup — enough for roughly 50 full scans of different targets. With the full scan you get:

  • Results from all 40+ parallel scanner engines, not just the passive surface check.
  • A detailed remediation guide for every finding, with code examples where applicable.
  • Exportable reports in SARIF (pipe straight to GitHub Security tab), CSV, and PDF.
  • Side-by-side scan comparison so you can track which vulnerabilities have been fixed between deployments.
  • Scheduled scans (daily, weekly, or monthly) with HMAC-signed webhook notifications when your score changes.
  • CI/CD integration via REST API and pre-built GitHub Actions workflows so every pull request is checked before merge.

Teams that want continuous security monitoring without managing their own scanner infrastructure will find the full scan especially useful. Instead of discovering a misconfiguration after a release, the Vuln0x pipeline check blocks the deploy and surfaces the finding inline in the pull request.

Explore more vulnerability scanner guides

The articles below go deeper on specific vulnerability types, tool comparisons, and scanning strategies. Whether you want to benchmark the best tools available in 2026, self-host an open-source scanner, or understand how Vuln0x compares to Nikto, OWASP ZAP, Burp Suite Community, Nuclei, WPScan, and Nessus, you will find a dedicated guide below.

Frequently asked questions

Is the website vulnerability scanner free?
Yes. The passive surface check is completely free — no account required. Enter your URL and get an A+ to F security grade in seconds. For the full 40+ scanner deep scan you sign up for a free account and receive 50 credits, still with no credit card needed.
Do I need to install anything?
Nothing at all. Vuln0x is a fully online website vulnerability scanner. You enter a URL in your browser and the scan runs on our servers. There is no agent, no browser extension, and no command-line tool to install.
How do I check a website for vulnerabilities?
Type your domain into the scanner above and click 'Scan free'. Within seconds you will see a security grade and a list of surface-level findings such as missing headers or an insecure TLS configuration. Register for a free account to unlock the full scan, which covers 40+ vulnerability categories including XSS, SQL injection, SSRF, exposed files, and more.
What is the best website vulnerability scanner?
For quick online checks, Vuln0x is the fastest option — no install, instant grade, and 40+ parallel scan engines. For local or CI/CD-heavy workflows, open-source tools like Nikto, OWASP ZAP, and Nuclei are popular alternatives. Our comparison guides cover each tool in depth so you can choose what fits your workflow.
Is online vulnerability scanning safe?
Yes. Vuln0x only sends the same HTTP requests a normal browser or search-engine crawler would send. We do not exploit vulnerabilities, modify your data, or disrupt your application. All network activity is read-only and passive unless you explicitly enable authenticated or active testing modes.

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