CVEs and KEVs share some similarities, but understanding their distinctions is key to enhancing your organization’s security posture.
To protect their organizations, cybersecurity professionals must understand and prioritize continually emerging vulnerabilities. In this ever-changing environment, two critical terms—CVE (Common Vulnerabilities and Exposures) and KEV (Known Exploited Vulnerabilities)—have become essential in guiding proactive defense strategies. While there are similarities between them, CVEs and KEVs serve distinct purposes and require different approaches and each plays a role in cybersecurity management. A comprehensive understanding of CVE vs KEV is critical so that you are clear on how each impact security strategies as well as on the actionable steps necessary to create and maintain a robust defense framework.
What is a CVE?
The Common Vulnerabilities and Exposures (CVE) system is a global standard for identifying and cataloging security vulnerabilities. Established in 1999 by the MITRE Corporation, the CVE system was developed to provide a consistent method for referencing vulnerabilities. A CVE identifier is assigned to each vulnerability as it is discovered, which allows cybersecurity teams to track, discuss, and share information about the issue across different platforms and tools.
CVE identifiers help cybersecurity professionals communicate about specific vulnerabilities without confusion, facilitating information sharing between industry players, researchers, and vendors. Each CVE entry is accompanied by a description, references, and a CVSS (Common Vulnerability Scoring System) score, which indicates the severity of the vulnerability on a scale from 0 to 10. These scores enable teams to prioritize vulnerabilities, focusing on those with the highest risk potential. Note that CVE and CVSS are not the same and that, just as CVE vs KEV is a critical distinction, CVE vs CVSS is as well.
The CVE lifecycle starts with vulnerability identification by a security researcher, vendor, or organization. Once identified, the following steps occur:
- Disclosure: The vulnerability is reported to the CVE Numbering Authority (CNA) or MITRE for assessment.
- Assignment: If the vulnerability meets the criteria, a CVE ID is assigned.
- Cataloging: The vulnerability is listed in the CVE database and made publicly available.
- Evaluation: Organizations assess the CVSS score and decide on mitigation or patching actions based on risk.
What is a KEV?
Known Exploited Vulnerabilities (KEV) represent a subset of vulnerabilities actively targeted by threat actors. The concept of KEV was introduced to highlight vulnerabilities that have not only been identified but are also being exploited in the wild. Because of their active status, when considering CVE vs KEV in your defense planning, remember that KEVs are considered higher priority than CVEs. They require immediate attention and mitigation from cybersecurity teams.
The CISA Known Exploited Vulnerabilities Catalog was created by the Cybersecurity and Infrastructure Security Agency (CISA) to serve as a live public resource for organizations to track and prioritize these high-risk vulnerabilities. This catalog provides detailed information about KEVs, including each vulnerability’s CVE ID, description, and any available remediation guidance. It’s a valuable resource that is continually updated to reflect the latest threats.
CVE vs KEV: Key Differences and Similarities
CVEs and KEVs share the common purpose of supporting cybersecurity professionals in tracking and addressing vulnerabilities, but they differ significantly in scope and application. By understanding these differences, security teams can better allocate resources, ensuring that KEVs are addressed immediately as the most pressing threats, while lower-risk vulnerabilities are evaluated and patched as needed.
Similarities Between CVEs and KEVs
- Identification and Tracking: Both systems identify vulnerabilities, making them trackable across cybersecurity tools and threat intelligence feeds.
- Standardization: CVEs and KEVs both provide a structured way to reference vulnerabilities, making collaboration and data sharing easier for security teams.
- Facilitation of Vulnerability Management: Each system enables professionals to prioritize actions based on the specific vulnerabilities relevant to their infrastructure.
CVE vs KEV – Notable Differences
- Scope: While CVEs cover all documented vulnerabilities across various platforms, KEVs focus exclusively on vulnerabilities that are being actively exploited. This difference makes KEVs a more immediate concern for cybersecurity teams.
- Urgency: KEVs are high-priority threats due to confirmed exploitation. They require faster response times than CVEs, which include vulnerabilities that might not currently be exploited but could pose a risk in the future.
- Curation and Updates: The CVE catalog is vast, with new entries added regularly to document a wide array of vulnerabilities. KEVs, in contrast, are highly curated and updated by CISA to reflect only those vulnerabilities posing immediate risk.
Proactive Cybersecurity Addresses CVEs and KEVs
Effective vulnerability management relies on understanding CVE vs KEV and using the data together to balance comprehensive coverage with prioritized actions. By leveraging both, cybersecurity teams can:
- Identify and Track Threats: CVE and KEV data collectively provide a 360-degree view of potential and active vulnerabilities.
- Prioritize Patching Efforts: KEV entries should be addressed urgently, as they represent threats that are actively impacting organizations. CVEs can be prioritized based on their CVSS scores and relevance to the organization’s infrastructure.
- Reduce Attack Surface: Addressing CVEs and KEVs allows teams to stay ahead of threat actors, limiting exploitable weaknesses within the system.
Best Practices for CVE and KEV Cybersecurity Management
Cybersecurity professionals should use the following best practices to incorporate CVE and KEV data into a robust vulnerability management strategy:
- Engage with Security Frameworks and Resources: Make use of frameworks like NIST and CISA’s guidelines to integrate vulnerability management best practices and receive up-to-date insights into managing vulnerabilities effectively.
- Implement Real-Time Monitoring and Alerts: Keep updated with real-time vulnerability feeds from CISA’s Known Exploited Vulnerabilities Catalog, MITRE’s CVE database, and other reputable sources. Automated alert systems help detect and respond to new CVEs and KEVs as they emerge.
- Prioritize Based on Threat and Impact: Use CVSS scores to assess the severity of CVEs, but prioritize KEVs due to their active exploitation status. Assign resources to patch or mitigate KEVs as a top priority, and address other CVEs based on their potential impact on your systems.
- Develop a Comprehensive Patching Strategy: Set a clear patching policy that distinguishes between different types of vulnerabilities. Regularly scheduled patching for general CVEs, combined with emergency patching procedures for KEVs, can keep your organization secure without overtaxing your team.
- Leverage Threat Intelligence and Automation: Automate the scanning and assessment of vulnerabilities to streamline the identification process. Threat intelligence platforms can help distinguish CVE vs KEV data and correlate that information with organizational risk profiles, ensuring that your security posture remains strong.
- Conduct Regular Vulnerability Assessments: Schedule assessments that scan for both CVEs and KEVs, validating that mitigations are effective and that new vulnerabilities are identified promptly.
- Limit Lateral Movement with Microsegmentation: Containing threats is critical in preventing attackers from moving laterally across your network once they exploit a vulnerability. Educate yourself on the difference between microsegmentation vs network segmentation, then restrict access, isolating sensitive systems and minimizing the spread of threats. Using CVE and KEV data, identify critical assets at risk and configure access controls to ensure that even if a vulnerability is exploited, attackers cannot easily access other systems or sensitive data.
- Adopt a Zero Trust Approach: Applying a zero trust framework requires verifying every access request, regardless of whether it originates from inside or outside the network. By aligning zero trust best practices with insights from CVE and KEV data, you can establish stringent verification measures around high-risk systems, regularly reassess access permissions, and enforce least-privilege principles. Zero Trust limits the potential impact of exploited vulnerabilities by requiring continuous validation for every user, device, and application attempting to interact with your network.
Take a Unified Approach to Vulnerability Management
As the threat landscape grows more complex, understanding the CVE vs KEV distinction will continue to be increasingly critical to effective vulnerability management. Cybersecurity professionals who leverage both CVE and KEV information are better able to prioritize resources, respond swiftly to active threats, and maintain a proactive defense posture.
Learn how TrueFort can support your vulnerability management initiatives. Request a demo today.
