In alphabetical order. Some are data sources, some are systems that mirror/scrape the data.
https://github.com/github/advisory-database
Notes: OSV 1.2.0
https://gitlab.com/gitlab-org/security-products/gemnasium-db
Notes: Yaml (e.g. use json2yaml?)
https://github.com/nexB/vulnerablecode/tree/main/vulnerabilities/importers
Notes: They have a whole python importer system, need to look into it