The Open Security Foundation (OSF) and Risk Based Security wrote an open letter to FIRST regarding the upcoming Common Vulnerability Scoring System (CVSS) version 3 proposal. While we were not formally asked to provide input, given the expertise of managing vulnerability databases, along with the daily use of CVSS, we felt the feedback would provide valuable insight to improve CVSS in the future.
Some of the areas discussed include:
- Introducing 4 levels for granularity
- Better definitions for terminology for more accurate scoring
- Re-examining the pitfalls of “Access Complexity”
- Limitations of the current Access Vector breakdown
- The challenge of scoring authentication
- And a variety of other considerations to improve vulnerability scoring
Our conclusion points to the need for CVSS to be overhauled as CVSSv2 has too many current shortcomings to provide an adequate and useful risk scoring model. You can download the full letter in PDF format.