It's a generic problem with using CVSS to score library vulnerabilities. CVSS is designed around complete systems, so it's totally crap to apply it to libraries.
I see a lot of critical (9+) supposed JavaScript "remote code execution with no authentication" CVEs being posted...
Right, if you are running it in an NPM server exposed to malicious user input with no authentication. Actually it runs client side in the browser and at best it's a prototype pollution vuln with a much lower score.