How EPSS Helps Security Professionals Prioritize Vulnerabilities

 EPSS (Exploit Prediction Scoring System)

The Exploit Prediction Scoring System (EPSS) is a data-driven framework designed to estimate the likelihood that a software vulnerability will be exploited in the wild. It helps security professionals prioritize which vulnerabilities to address first based on real-world risk, rather than just severity.

What EPSS Measures

EPSS provides a probability score (0 to 1) indicating how likely it is that a vulnerability will be exploited within a short time frame (typically the next 30 days). For example:

• EPSS Score of 0.6 means there's a 60% chance of exploitation.
• EPSS Score of 0.01 means there's only a 1% chance.

How EPSS Works

EPSS uses machine learning models trained on:

• CVE metadata (e.g., CVSS scores, affected software)
• Exploit availability (e.g., public exploit code)
• Threat intelligence feeds
• Historical exploitation data

This allows EPSS to dynamically assess risk based on current trends and attacker behavior.

Why EPSS Is Useful

• Prioritization: Helps focus remediation efforts on vulnerabilities most likely to be exploited.
• Complement to CVSS: CVSS measures severity, but not exploit likelihood. EPSS fills that gap.
• Real-world relevance: Based on actual exploitation data, not theoretical risk.

EPSS vs CVSS

Use Cases

• Vulnerability management: Prioritize patching based on EPSS scores.
• Risk assessment: Combine EPSS with asset value and exposure.
• Threat modeling: Identify high-risk vulnerabilities in attack paths.