What is naabu?

Naabu is a command-line tool for port scanning, which means it checks a list of computers or servers to find out which network ports are open and accepting connections. Security researchers and penetration testers use this kind of tool during assessments to map out what services are exposed on a target system before deciding where to look more closely. The tool is written in Go and is designed to be fast and lightweight. It can send different types of network probes (SYN, CONNECT, and UDP) and works with both IPv4 and IPv6 addresses. You can give it a single host, a list of hosts, a range of IP addresses, or an ASN number (a grouping identifier used by large networks), and it will return a list of which ports responded. Naabu includes a feature to skip full scans for content delivery networks and firewalls, since those systems sit in front of the actual target and would otherwise flood results with irrelevant ports. It can also pull passive port data from Shodan's public database without sending any packets at all. For deeper analysis, it can call Nmap automatically on the ports it finds, which is a separate tool that identifies what software is running on each port. Results can be written as plain text, JSON, or CSV. The tool supports a configuration file so you do not have to repeat flags on every run. It integrates with the ProjectDiscovery cloud platform, which is the company behind this tool, allowing results to be uploaded to a shared dashboard. The project is open source under the MIT license and is part of a broader suite of security tools maintained by ProjectDiscovery. It is intended for use in authorized security testing, bug bounty programs, and penetration tests.