This is a quickie parsing of the current CNA list, broken out by Top-Level Root (TLR), then by Root. Currently, there's only two top-level roots, the MITRE Corporation and CISA. But, if you see a third here, that means there's a new TLR, or more likely, a typo in one of the existing ones.
This list pulls directly from MITRE's published data, but this website is quite definitely an unofficial, probably error-prone parsing of that data. If you notice any bugs, you should report those to my GitHub repo, here.