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NIST IR 8409 (Initial Public Draft)

Measuring the Common Vulnerability Scoring System Base Score Equation

Date Published: June 8, 2022
Comments Due: July 29, 2022 (public comment period is CLOSED)
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Peter Mell (NIST), Jonathan Spring (CERT/CC at Carnegie Mellon University), Srividya Ananthakrishna (Huntington Ingalls Industries), Francesco Casotto (Cisco), Dave Dugal (Juniper), Troy Fridley (AcuityBrands), Christopher Ganas (Palo Alto Networks), Arkadeep Kundu (Cisco), Phillip Nordwall (Dell), Vijayamurugan Pushpanathan (Schneider Electric), Daniel Sommerfeld (Microsoft), Matt Tesauro (Open Web Application Security Project), Christopher Turner (NIST)


Calculating the severity of information technology vulnerabilities is important for prioritizing vulnerability remediation and helping to understand the risk of a vulnerability. The Common Vulnerability Scoring System (CVSS) is a widely used approach to evaluating properties that lead to a successful attack and the effects of a successful exploitation. CVSS is managed under the auspices of the Forum of Incident Response and Security Teams (FIRST) and is maintained by the CVSS Special Interest Group (SIG). Unfortunately, ground truth upon which to base the CVSS measurements has not been available. Thus, CVSS SIG incident response experts maintain the equations by leveraging CVSS SIG human expert opinion.

This work evaluates the accuracy of the CVSS “base score” equations and shows that they represent the CVSS maintainers' expert opinion to the extent described by these measurements. NIST requests feedback on the approach, the significance of the results, and any CVSS measurements that should have been conducted but were not included within the initial scope of this work. Finally, NIST requests comments on sources of data that could provide ground truth for these types of measurements.

NOTE: A call for patent claims is included on page iv of this draft. For additional information, see Information Technology Laboratory (ITL) Patent Policy – Inclusion of Patents in ITL Publications.




computer; Common Vulnerability Scoring System; error; expert opinion; measurement; measuring; metrics; network; scoring; security
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Supplemental Material:
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Document History:
06/08/22: IR 8409 (Draft)
11/15/22: IR 8409 (Final)


Security and Privacy

security measurement, vulnerability management