Findomain
Fast open source tool for discovering and monitoring domain subdomains
...By querying multiple passive data sources in parallel, the tool can identify a large number of subdomains within a short time, making it useful for security researchers, penetration testers, and bug bounty hunters. Findomain aggregates information from various online services to provide a comprehensive list of discovered subdomains without directly attacking the target infrastructure. The tool also supports monitoring capabilities that allow users to track newly discovered subdomains and send alerts through integrations such as messaging platforms. ...