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The Common Configuration Scoring System (CCSS): Metrics for Software Security Configuration Vulnerabilities



Peter M. Mell, Karen Scarfone


The Common Configuration Scoring System (CCSS) is a set of measures of the severity of software security configuration issues. CCSS is derived from the Common Vulnerability Scoring System (CVSS), which was developed to measure the severity of vulnerabilities due to software flaws. CCSS can assist organizations in making sound decisions as to how security configuration issues should be addressed and can provide data to be used in quantitative assessments of the overall security posture of a system. This report defines proposed measures for CCSS and equations to be used to combine the measures into severity scores for each configuration issue. The report also provides several examples of how CCSS measures and scores would be determined for a diverse set of security configuration issues.
NIST Interagency/Internal Report (NISTIR) - 7502
Report Number


security configuration, security measurement, vulnerability measurement, vulnerability scoring


Mell, P. and Scarfone, K. (2010), The Common Configuration Scoring System (CCSS): Metrics for Software Security Configuration Vulnerabilities, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 14, 2024)
Created December 27, 2010, Updated June 2, 2021