A frontend JS library vulnerability scanner is a security tool that checks the versions of JavaScript libraries used in your web application against a database of known Common Vulnerabilities and Exposures (CVEs). It helps developers identify outdated or vulnerable libraries like jQuery, React, Lodash, Bootstrap, and others that may expose their website to cross-site scripting (XSS), prototype pollution, or other client-side attacks.

It's recommended to scan your JavaScript libraries every time you deploy new code or at least once a month. New CVEs are published regularly, and a library that was safe last month could have a critical vulnerability discovered today. Integrating automated vulnerability scanning into your CI/CD pipeline is the best practice for enterprise applications.

Our vulnerability database covers 25+ popular frontend JavaScript libraries including jQuery, React, Vue.js, AngularJS, Bootstrap, Lodash, Axios, Moment.js, D3.js, PostCSS, Semver, url-parse, Browserslist, set-value, object-path, y18n, ini, word-wrap, and more. We track over 30 real CVE records with severity ratings from LOW to CRITICAL, each linked to official NVD (National Vulnerability Database) entries.

If a vulnerability is detected, you should immediately upgrade the affected library to the recommended fix version. Each vulnerability report includes the minimum patched version. For example, if jQuery 3.4.1 has CVE-2020-11023 (XSS), upgrading to jQuery 3.5.0 or later resolves the issue. Always test upgrades in a staging environment before deploying to production.

CVE (Common Vulnerabilities and Exposures) is a standardized identifier for publicly known security vulnerabilities. Each CVE has a CVSS (Common Vulnerability Scoring System) score from 0 to 10, determining severity: LOW (0.1-3.9), MEDIUM (4.0-6.9), HIGH (7.0-8.9), and CRITICAL (9.0-10.0). Our scanner displays both the CVE ID and severity level so you can prioritize fixes accordingly.

The URL scanner in this free online tool performs a simulated scan to demonstrate typical vulnerability patterns. For complete and accurate scanning of arbitrary websites, a server-side component is needed to fetch and analyze the actual page source, script tags, and bundled JavaScript. We recommend using the Manual Version Check tab for precise verification of specific library versions you're using.

Yes, this vulnerability scanner is free to use for both personal and commercial projects. The vulnerability database is curated from publicly available CVE records. For enterprise needs with automated scanning, API access, and CI/CD integration, consider using additional tools like Snyk, OWASP Dependency-Check, or npm audit alongside our manual checker.