projectdiscovery/nuclei

Nuclei is a vulnerability scanner: a tool that probes websites, APIs, networks, DNS configurations, and cloud setups looking for known security weaknesses. What distinguishes it from a generic scanner is that the checks themselves are not hard-coded inside the program. Each check is written as a short YAML file, called a template, that describes exactly what request to send and what response would indicate a vulnerability. YAML is just a plain-text format for structured data, easy to read and edit. Because templates are simple files, a global community of security professionals contributes them, and the project says this approach is designed to produce zero false positives by mimicking the real steps an attacker would take. In practice you point Nuclei at one URL, a list of targets, or a network address, and it runs many templates in parallel, grouping similar requests together for speed. It supports a wide range of protocols including HTTP, TCP, DNS, SSL, WHOIS, and embedded JavaScript and code execution checks. A separate, community-maintained library of templates ships alongside the scanner, and the tool can be plugged into continuous integration pipelines so the same checks run automatically on every code change. Findings can be sent on to Jira, Splunk, GitHub, Elastic, and GitLab. This is the kind of tool a penetration tester, security team, or developer would reach for when they need to repeatedly check a stack of services for known issues. Nuclei is a command-line program written in Go, and the project also offers a paid cloud edition with team features. The full README is longer than what was provided.