A free cybersecurity knowledge hub built for security researchers, penetration testers, and anyone learning to secure the digital world. Real-time vulnerability data, curated tools, technical writeups, and structured learning — all in one place.
4nuxd.one is a cybersecurity platform owned and maintained by Anurag Kumar (4nuxd). It aggregates vulnerability intelligence, security tooling references, and educational resources into a single, searchable interface — built by a security researcher, for security researchers.
The platform pulls CVE data directly from the NIST National Vulnerability Database, organizes it with CVSS scoring and severity analysis, and pairs it with a comprehensive CWE catalog to help you understand not just what vulnerabilities exist — but why they happen and how to fix them.
Beyond vulnerability data, you'll find a curated arsenal of 55+ security tools, reference cheat sheets for common attack techniques, and structured learning paths from beginner to advanced.
All resources are free to access. No paywalls, no premium tiers. Security knowledge should be accessible to everyone.
CVE data is sourced directly from NIST NVD. Writeups are based on real engagements. Tools are tested and verified.
Vulnerability data syncs automatically. New tools and techniques are added regularly to keep the platform relevant.
Built for security professionals, students, and enthusiasts. Contributions, feedback, and collaboration are always welcome.
Real-time vulnerability tracking powered by the NVD API. Search, filter, and analyze CVEs with CVSS scoring, severity breakdowns, and affected product mapping. New vulnerabilities are synced automatically.
Complete Common Weakness Enumeration reference with categorized vulnerability classes, real-world examples, and mitigation strategies. Understand the root causes behind CVEs.
Technical writeups covering penetration testing engagements, CTF solutions, vulnerability research, and attack chain analysis. Written from real-world experience.
Curated catalog of 55+ cybersecurity tools across 11 categories — from reconnaissance and exploitation to forensics and cloud security. Each tool includes platform info, use cases, and direct links.
Quick-reference guides for penetration testing techniques, common attack vectors, and security methodologies. Organized by topic with key commands and syntax.
Structured roadmaps for cybersecurity careers — from beginner fundamentals to advanced red teaming and cloud security. Step-by-step progression with recommended resources.
Found a bug, have a feature request, or want to collaborate on security research? Reach out.
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