Machinae is a tool for collecting intelligence from public sites/feeds about various security-related pieces of data: IP addresses, domain names, URLs, email addresses, file hashes and SSL fingerprints. It was inspired by Automater, another excellent tool for collecting information. The Machinae project was born from wishing to improve Automater in 4 areas:

Extract and aggregate threat intelligence. An extendable tool to extract and aggregate IOCs from threat feeds.

ThreatIngestor can be configured to watch Twitter, RSS feeds, or other sources, extract meaningful information such as malicious IPs/domains and YARA signatures, and send that information to another system for analysis.

Microsoft Threat Intelligence Python Security Tools. msticpy is a library for InfoSec investigation and hunting in Jupyter Notebooks.

A free, community-sourced, machine-readable knowledge base of digital forensic artifacts that the world can use both as an information source and within other tools.

If you'd like to use the artifacts in your own tools, all you need to be able to do is read YAML. That is it, no other dependencies. The Python code in this project is just used to validate all the artifacts to make sure they follow the specification.

A distributed vulnerability database for Open Source.
An open, precise, and distributed approach to producing and consuming vulnerability information for open source.

Weekly Security Vulnerability Emails.
Follow Security Vulnerabilities in your software stack.
Every month about 2,000 vulnerabilities are published, but how many of those are important to you?
Use StackWatch to create a software stack (a list of software you use), then get a weekly email with security vulnerabilities that have been published for software within your stack.

Find & Fix Open Source vulnerabilities.
Get real-time security alerts and compliance issues
on your open source dependencies
within Azure DevOps or GitHub.

Open Source Threat Intelligence Platform & Open Standards For Threat Information Sharing

Open Cyber Threat Intelligence Platform.
OpenCTI is an open source platform allowing organizations to manage their cyber threat intelligence knowledge and observables. It has been created in order to structure, store, organize and visualize technical and non-technical information about cyber threats.