CVEs with an EPSS score above 30%

The Exploit Prediction Scoring System (EPSS) estimates the probability that a CVE will be exploited in the wild in the next 30 days, from 0 to 100%. FIRST.org publishes a new score for every published CVE each day, using a model trained on observed exploitation activity.

The percentile ranks a CVE's score against every other CVE's. A CVE in the 95th percentile scores higher than 95% of all CVEs, even when its probability looks small, because most CVEs score well under 1%. For example, a CVE with EPSS 0.42 and percentile 0.99 has a 42% chance of exploitation within 30 days and scores higher than 99% of CVEs.

CVSS measures how severe a vulnerability would be if exploited; EPSS measures how likely exploitation is. A CVSS 9.8 bug nobody targets can have an EPSS under 1%, while a CVSS 6.5 bug in a widely scanned product can score above 50%. Use both: CVSS for impact, EPSS for likelihood.

There is no single cutoff. Many teams prioritize CVEs above 10% (roughly the top 4% of all CVEs) and treat anything above 30% as urgent. cve.now flags a high-severity CVE as critical once its EPSS reaches 10%.

KEV lists vulnerabilities already exploited; EPSS predicts which will be. Patch everything on KEV first, then work down by EPSS score, starting with the highest-severity CVEs in your stack.