Vulnerabilities
EPSS (Exploit Prediction Scoring System)
Also known as: EPSS score
Definition
A data-driven model, maintained by FIRST, that estimates the probability a given CVE will be exploited in the wild within the next 30 days.
Examples
- A CVE with EPSS probability 0.97 and percentile 99 — almost certainly being exploited.
- A 9.8 CVSS bug with EPSS 0.001 — severe but unlikely to be attacked imminently.
Related terms
CVE (Common Vulnerabilities and Exposures)
A public catalogue that assigns a unique identifier to each disclosed software or hardware vulnerability so they can be referenced unambiguously across the industry.
CVSS (Common Vulnerability Scoring System)
An open framework, maintained by FIRST, that produces a 0–10 severity score for a vulnerability based on its exploitation characteristics and impact.
Known Exploited Vulnerability (KEV)
A CVE that the U.S. CISA confirms is being actively exploited and adds to its public KEV Catalog, triggering remediation deadlines for U.S. federal agencies.
Vulnerability
A weakness in a system, application, or process that an attacker can exploit to violate confidentiality, integrity, or availability.
Threat Intelligence
Evidence-based knowledge about threats and threat actors — including indicators, TTPs and context — used to guide security decisions and detection.
Patch Management
The end-to-end process of identifying, testing, deploying, and verifying software updates that fix vulnerabilities or bugs.