The Common Vulnerability Scoring System (CVSS) is a framework for rating the severity of computer system vulnerabilities. Scores are calculated from metrics that approximate the ease and impact of exploits. Scores range from 0 (minor) to 10 (severe). While many use only the CVSS Base score for determining severity, temporal and environmental scores also exist, to account for the availability of mitigations and the number of vulnerable systems within an organization, respectively.