EPSS Explained: Why Exploit Prediction Scoring Changes Everything for Vulnerability Prioritization

Your security scanner just flagged 847 vulnerabilities. Your team can fix 20 this sprint. Which 20? If your answer is "the ones with the highest CVSS scores," you're using an imperfect heuristic that leaves your real attack surface exposed while you remediate vulnerabilities that will never be exploited. The Problem with CVSS Alone CVSS measures theoretical severity: how bad would this be if exploited? What it doesn't measure is likelihood: how probable is it that this vulnerability will actually be exploited? Fewer than 5% of published CVEs are ever observed being exploited in the wild. A CVSS 9.8 vulnerability with no public exploit code may sit indefinitely unexploited. Meanwhile, a CVSS 6.5 vulnerability that's trivial to exploit may be actively used in attacks within days. What EPSS Is The Exploit Prediction Scoring System assigns each CVE a probability score between 0 and 1 representing the likelihood of exploitation within the next 30 days. The model uses: Exploit availability.