CVSS is the short form of Common Vulnerability Scoring System, a standardized scoring system used to assess and compare the severity of security vulnerabilities. It provides an objective, quantitative measure of the potential impact of a vulnerability by assigning numerical scores based on different metrics.
The CVSS score helps security professionals prioritize their vulnerability remediation efforts. It is widely used in the cybersecurity industry and is often used as a reference point by organizations when making decisions about patching or mitigating vulnerabilities.
The Common Vulnerability Scoring System (CVSS) score can greatly assist an organization in assessing and prioritizing security vulnerabilities effectively. For instance, let's consider an organization that manages a web application. When a new security vulnerability is discovered, the organization can use the CVSS score to quantitatively measure the severity of the vulnerability based on its impact, exploitability, and complexity. With this score, they can prioritize their response efforts, addressing high-scoring vulnerabilities first. This enables the organization to allocate their limited resources efficiently, focusing on the most critical threats that pose a significant risk to their systems, thus enhancing their overall security posture. By utilizing CVSS scores, organizations can make informed decisions, proactively address potential risks, and mitigate security breaches effectively.
Official NCD CVSS v3 & v4 Calculator:
Components of CVSSv3:
1. Base Score:
The Base Score represents the intrinsic qualities of the vulnerability and does not take into account any temporal or environmental factors. It is calculated based on three metric groups:
a. Exploitability (Attack Vector, Attack Complexity, Privileges Required, User Interaction):
These metrics assess how easy it is for an attacker to exploit the vulnerability and gain access to the target system.
b. Impact (Confidentiality, Integrity, Availability):
These metrics evaluate the potential impact on the target system if the vulnerability is exploited, considering the loss of data confidentiality, data integrity, and system availability.
2. Temporal Score:
The Temporal Score captures the characteristics of the vulnerability that may change over time, such as the availability of a patch or the likelihood of the vulnerability being actively exploited. It consists of three metrics:
a. Exploit Code Maturity:
This metric reflects the maturity level of existing exploits, ranging from "Not Defined" to "High."
b. Remediation Level:
This metric indicates the availability and practicality of official or temporary fixes, patches, or mitigations, ranging from "Not Defined" to "Official Fix."
c. Report Confidence:
This metric expresses the confidence level in the existence and accuracy of the vulnerability report, ranging from "Unknown" to "Confirmed."
3. Environmental Score:
The Environmental Score accounts for the unique characteristics of a specific organization's environment. It helps tailor the CVSS score to the individual situation by considering factors like the system's importance, whether the vulnerability is exposed to external networks, and the impact of the vulnerability on the organization. This score has two metrics:
a. Confidentiality Requirement (CR):
This metric represents the importance of maintaining data confidentiality within the organization, ranging from "Low" to "High."
b. Integrity Requirement (IR):
This metric reflects the importance of maintaining data integrity within the organization, ranging from "Low" to "High."
The Environmental Score is calculated by modifying the Base Score according to the impacts specific to an organization's environment. It is not a required component, but it can provide a more personalized risk assessment.
By combining the Base, Temporal, and Environmental scores, organizations can determine the severity of a vulnerability and prioritize their efforts to address the most critical security issues first.