OWASP's Amass Project. I'm not quite sure what it does based on the docs, so I thought if I posted then a kindly soul might enlighten me.
From the docs:
> OWASP Amass is an open-source, versatile attack surface intelligence framework designed to comprehensively map an organization’s footprint. Built for flexibility and depth, Amass combines advanced data collection, network mapping, and OSINT capabilities to deliver detailed insights into physical and digital assets.
