The Exploit Prediction Scoring System (EPSS) is a technical standard managed by FIRST for estimating the probability a publicly disclosed software vulnerability will be exploited in the wild within the next 30 days.[1][2] EPSS is complementary to the Common Vulnerability Scoring System.[1] Combining EPSS and CVSS aligns remediation with actual threat activity.[3][4]
| EPSS | |
|---|---|
| Exploit Prediction Scoring System | |
| Year started | 2021 |
| Latest version | Version 4 |
| Organization | FIRST |
| Domain | Information security |
| Website | www |
Characteristics
editVulnerabilities get assigned a probability value between 0 and 1 that determines the chance of them being exploited in the real world.[5]
History
editThe original concept and prototype were presented by researchers Michael Roytman, Jay Jacobs, and Sasha Romanosky at Black Hat in 2019.[6] In April 2020 FIRST started a special interest group to develop the standard.[7]
Versions
edit- 7 January 2021 – Public publication of daily EPSS scores began (model v1).[8]
- 4 February 2022 – Version 2 incorporated additional telemetry sources and algorithmic improvements.
- 7 March 2023 – Version 3 introduced gradient-boosted decision trees and expanded feature sets.
- 17 March 2025 – Version 4 added contextual threat-intelligence feeds and performance gains.[1]
Adoption
editThe U.S. Cybersecurity and Infrastructure Security Agency (CISA) encourages using EPSS alongside its Known Exploited Vulnerabilities Catalog for patch triage.[9] Major vulnerability-management platforms, such as Rapid7, Tenable, and Qualys, integrate EPSS scores for risk-based patching.[6] Academic research uses EPSS to model exploit trends and evaluate defenses.[10]
References
edit- 1 2 3 "EPSS Version 4 Released". FIRST. 17 March 2025. Retrieved 14 April 2025.
- ↑ Kovacs, Eduard (2025-05-20). "Vulnerability Exploitation Probability Metric Proposed by NIST, CISA Researchers". SecurityWeek. Retrieved 2026-03-15.
- ↑ Jiang, Yuning; Oo, Nay; Meng, Qiaoran; Hoon Wei Lim; Sikdar, Biplab (12 February 2025). "A Survey on Vulnerability Prioritization: Taxonomy, Metrics, and Challenges". arXiv:2502.11070 [cs.CR].
- ↑ Ravalico, Damiano; Farina, Mauro; Trevisan, Martino; Bartoli, Alberto (2025). "Analysing the Temporal Dynamics of the Exploit Prediction Scoring Systems (Epss)". doi.org. Retrieved 2026-03-15.
- ↑ "Exploit Prediction Scoring System (EPSS) Special Interest Group (SIG)". FIRST — Forum of Incident Response and Security Teams. Retrieved 2026-04-16.
- 1 2 "What Is an EPSS Score?". Brinqa. 10 February 2024. Retrieved 14 April 2025.
- ↑ "EPSS Special Interest Group Portal". FIRST. Retrieved 14 April 2025.
- ↑ "Understanding and Using the EPSS Scoring System". FOSSA Blog. 20 January 2023. Retrieved 14 April 2025.
- ↑ Parla, Rianna (4 November 2024). "Efficacy of EPSS in High Severity CVEs Found in CISA KEV". arXiv:2411.02618 [cs.CR].
- ↑ Mell, Peter; Bojanova, Irena; Galhardo, Carlos (1 May 2024). "Measuring the Exploitation of Weaknesses in the Wild". arXiv:2405.01289 [cs.CR].