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CVSS Implementation Guidance



Joshua M. Franklin, Charles W. Wergin, Harold Booth


This Interagency Report provides guidance to individuals scoring vulnerabilities using the Common Vulnerability Scoring System (CVSS) Version 2.0 scoring metrics. CVSS defines a vulnerability as a bug, flaw, weakness, or exposure of an application, system device, or service that could lead to a failure of confidentiality, integrity, or availability [12]. The guidance in this document is the result of applying the CVSS specification to score over 50,000 vulnerabilities analyzed by the National Vulnerability Database (NVD). An overview of the CVSS base metrics is first presented followed by guidance for difficult and/or unique scoring situations. To assist vulnerability analysts, common keywords and phrases are identified and accompanied by suggested scores for particular types of software vulnerabilities. The report includes a collection of scored vulnerabilities from the NVD, alongside a justification for the provided score. Finally, this report contains a description of the NVD’s vulnerability scoring process.
NIST Interagency/Internal Report (NISTIR) - 7946
Report Number


Common Vulnerability Scoring System Version 2.0, CVSS v2.0, National Vulnerability Database, NVD, security metrics, vulnerabilities, vulnerability scoring


Franklin, J. , Wergin, C. and Booth, H. (2014), CVSS Implementation Guidance, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 17, 2024)


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Created April 28, 2014, Updated May 4, 2021