> - Firstly, you quickly realise how irrelevant CVSS scores are
Even if you factor in the environmental score? I realize it's a lot more work, but it basically allows you to tune the score to get any value you want.
I could reword that CVSS is useless on its own - EPSS takes CVSS as an input afterall. The point here is that applying environmental scoring is the hard part. That's the algorithm that's containing the complexity.
Imagine a YAML parsing library that can cause an out-of-memory exception if you give it a YAML file greater than 3 megabytes.
If you're an online service where untrusted users can submit arbitrary YAML, and an out-of-memory exception is a severe problem, then it's severity 10.
If you're an online service that doesn't use yaml in any way, but your web framework bundled the library as a transitive dependency because yaml is one of their five supported configuration options, then it's severity 2.
The problem is figuring out which of those situations you're in takes a load of time - and the flow of CVEs is endless, as CVE numbers are given out like candy at halloween. Often it's quicker to just update to the latest version of the YAML library.