Part 1 — Taming the Vulnerability Flood: How EPSS Helps Cybersecurity Leaders Focus on Real Threats

The Rising Tide of Vulnerabilities

Every week seems to bring news of another software vulnerability. Security teams scramble to patch critical systems, and executives are left wondering which vulnerability could become the next breach headline. The truth is that no organization can fix every flaw immediately — not when the number of known vulnerabilities has already surpassed a quarter million (271,000-plus as of March 2025) and grew by about 41% from 2023 to 2024. It’s a flood, and trying to plug every leak isn’t realistic.

Yet, only a small fraction of these vulnerabilities will ever be exploited by attackers. Roughly 6% of published vulnerabilities have been observed being exploited in the wild. In other words, out of thousands of new security issues, only a handful turn into actual cyber incidents. The challenge for leadership is identifying those dangerous few in advance. Historically, companies relied on severity scores like CVSS to gauge risk. But severity is not the same as risk — a “critical” vulnerability might never be touched by attackers, while a “medium” one might become the entry point for a major breach. This is where the Exploit Prediction Scoring System comes in.

What is EPSS (Exploit Prediction Scoring System)?

EPSS is essentially a data-driven crystal ball for cybersecurity teams. Developed by an industry consortium led by FIRST (the same organization behind CVSS), it estimates the likelihood that a given vulnerability will be exploited in the near term. In non-technical terms, EPSS tells you, “What’s the chance attackers will actually use this flaw against someone?” The system draws on real-world cyber threat data — exploit code sightings, attacks observed by sensors, discussions in hacker forums — and uses machine learning to output a probability from 0 to 1 (or 0% to 100%). A higher EPSS score means a higher chance that bad actors will leverage that vulnerability in an attack.

Importantly, EPSS scores are updated daily to reflect the latest intelligence. Unlike static risk ratings, EPSS keeps up with shifting attacker focus. If hackers suddenly start exploiting a vulnerability that was quiet before, the EPSS score will rise. If a flaw fades out of hacker attention, its score can drop.

And EPSS isn’t a niche academic experiment — it’s rapidly becoming essential cybersecurity infrastructure. Dozens of vendors (over 60 on FIRST’s public adopter list) have integrated EPSS into their products, and a growing community of enterprises rely on its insights. The model has been refined through multiple versions since 2018 and consistently improved its predictive power. By 2023, studies showed EPSS could correctly distinguish exploited vs. non-exploited issues about 80% of the time, and later versions have only gotten better. For executives, this means EPSS is a mature, vetted approach, not theoretical pixie dust.

Why Executives Should Care

From a leadership perspective, EPSS offers a way out of “patch everything” paralysis. It shifts the conversation from “How do we fix thousands of vulnerabilities?” to “Let’s focus on the few that matter most right now.” This focused approach has concrete benefits for the business:

• Efficient Risk Reduction: By tackling the vulnerabilities most likely to be used in an attack, you dramatically reduce the organization’s true risk exposure with far less effort. Security teams aren’t chasing ghosts; they’re fixing the issues attackers are actually eyeing.
• Optimized Use of Resources: Patching and testing updates consume time, money, and can even cause downtime. EPSS helps ensure those resources are spent where they yield the highest security ROI. One study found that using EPSS to prioritize fixes can cut the workload by more than 80% while achieving the same risk coverage.
• Proactive Decision-Making: Executives can move from a reactive stance to a proactive strategy driven by data. It’s similar to weather forecasting: you don’t cancel an event for a 5% chance of rain, but you certainly would for a 70% chance. EPSS provides that forecast for cyber attacks.
• Cross-Industry Relevance: Whether you run IT for a mental health clinic, a tribal casino, a private school, or a multinational bank, EPSS adapts to your context. It’s built on global threat intelligence, so it captures trends that affect every sector.

Consider a quick example. A mental health services provider with limited IT staff faces thousands of new vulnerability alerts each year. By applying EPSS, the IT director discovers that out of 50 “high” severity findings this month, only 5 have an EPSS score above 5%. Those 5 become the top priority for immediate patching. The others — still important — can be scheduled into routine maintenance. The result: the most dangerous vulnerabilities are neutralized before they can be used to compromise patient records, and the organization isn’t burning out its team chasing every theoretical hole in the fence.

Addressing the “What If We’re Wrong?” Scenario

No prediction system is perfect. As an executive, you might worry: what if EPSS tells us a vulnerability is low-risk, and it gets exploited anyway? It’s a fair question. There will always be edge cases, but these cases are the exception, not the rule, and EPSS is designed to adapt quickly when the unexpected happens.

The moment there’s evidence that attackers are gravitating toward a vulnerability — new exploit code published, a spike in attacks on that CVE — the EPSS score will update accordingly, and your team can react. Organizations should never rely on EPSS alone; defense in depth is still key. Even “low EPSS” vulnerabilities aren’t ignored forever — they’re monitored and eventually patched as part of your regular cycle, while other controls (firewalls, intrusion detection, network segmentation, backups) provide safety nets in the meantime.

Remember that EPSS is continuously validated by the community. In one analysis, remediating vulnerabilities with an EPSS score above 0.6 achieved about 80% efficiency — meaning 8 out of 10 of those fixes were indeed targeting vulnerabilities that saw real attacks. Those are odds any security leader would take in an uncertain threat landscape.

Turning Insight into Action

In the end, EPSS empowers executives and managers to make smarter, faster security decisions. It’s about doing the right things sooner, rather than doing everything haphazardly. By focusing your limited time and budget on the vulnerabilities that are actually likely to bite, you reduce the chance of a breach in a measurable, defensible way.

The vulnerability flood isn’t slowing down, but with EPSS, you gain a way to channel those floodwaters toward what truly matters. For any leader tasked with safeguarding their organization in today’s threat environment, that clarity is worth its weight in gold.

Tame the flood. Prioritize what matters. Sleep better tonight. Stop drowning in CVEs — let our EPSS-driven experts show you exactly which vulnerabilities put your business on the line before attackers do. Book a no-obligation, 20-minute Risk-Cut Session and we’ll map your top-priority fixes and send you a quick-win action plan.