CVE Prioritization – NVD CVSS + CISA KEV + EPSS Risk Triage for Patch Management

Turn a list of CVE IDs, a keyword search or the latest CISA Known Exploited Vulnerabilities into a prioritized patch list, enriched with NVD CVSS/CWE, KEV status and FIRST EPSS exploit probability.

Why: CVSS alone ranks too many things "critical". Combining known exploited (KEV) and likely to be exploited (EPSS) lets security and IT teams patch the short list first.

CVE priority tiers (KEV, EPSS, CVSS)

P1-exploited (in CISA KEV) → P2-likely (EPSS ≥ 0.10) → P3-severe (CVSS ≥ 9.0) → P4-high (CVSS ≥ 7.0) → P5-routine; UNSCORED if NVD/EPSS have no data yet. The reason for each tier is in priorityReason. The rules are a transparent heuristic (not a vendor standard) and live in src/priority.js.

Input: CVE IDs, keyword or recent KEV additions

Field	Description
cveIds	List of CVE IDs (invalid IDs are skipped with a warning).
keywordSearch	NVD keyword search, e.g. "apache tomcat".
publishedWithinDays	CVEs published in the last N days.
kevAddedWithinDays	CVEs added to CISA KEV in the last N days.
onlyKnownExploited, minCvss, minEpss	Filters.
maxResults	Cap per run (default 50).
nvdApiKey	Optional free NVD API key (secret). Without it the Actor waits ~6.5 s per NVD call to respect the public limit of 5 requests / 30 s.

{ "cveIds": ["CVE-2021-44228"], "kevAddedWithinDays": 2, "maxResults": 6 }

Output: one enriched record per CVE

{
  "cveId": "CVE-2021-44228",
  "priority": "P1-exploited",
  "priorityReason": "Listed in CISA Known Exploited Vulnerabilities catalog",
  "cvss": { "version": "3.1", "baseScore": 10, "severity": "CRITICAL" },
  "weaknesses": ["CWE-20", "CWE-400", "CWE-502", "CWE-917"],
  "epss": { "score": 0.99999, "percentile": 1, "date": "2026-10-29" },
  "knownExploited": true,
  "kev": { "dateAdded": "2021-12-10", "dueDate": "2021-12-24", "knownRansomwareCampaignUse": "Known" }
}

Real sample run: samples/output.json.

CVE triage pricing (pay per CVE)

$0.004 per CVE enriched. 1,000 CVEs = $4.

Data sources, credits and notices

This product uses the NVD API but is not endorsed or certified by the NVD. KEV data: CISA Known Exploited Vulnerabilities Catalog. EPSS scores: FIRST.org. Not security advice; validate against your own asset inventory.

Related searches: CVE lookup, NVD API, CISA KEV, EPSS score, vulnerability prioritization, patch prioritization, security advisory feed.

Run via API (cURL)

curl -X POST "https://api.apify.com/v2/acts/exprmntl~cve-risk-triage-kev-epss/run-sync-get-dataset-items?token=YOUR_APIFY_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"cveIds": ["CVE-2021-44228", "CVE-2024-3400"]}'

Run from Python

from apify_client import ApifyClient

client = ApifyClient("YOUR_APIFY_TOKEN")
run = client.actor("exprmntl/cve-risk-triage-kev-epss").call(run_input={"cveIds": ["CVE-2021-44228", "CVE-2024-3400"]})
for item in client.dataset(run["default_dataset_id"]).iterate_items():
    print(item)

Running with no input performs a small demo run with example data.

FAQ

How do I prioritize CVEs from a vulnerability scan? Export the CVE IDs from your scanner and pass them in cveIds. Each CVE gets CVSS, KEV status, EPSS and a priority tier.

What is EPSS and why combine it with KEV? EPSS (FIRST) estimates the probability a CVE is exploited in the next 30 days; CISA KEV lists CVEs already exploited. Together they beat CVSS alone for patch ordering.

Can I get newly added CISA KEV vulnerabilities? Yes. Set kevAddedWithinDays (e.g. 7) for a weekly KEV digest; schedule the Actor for automatic reports.

Do I need an NVD API key? No, but adding nvdApiKey makes large runs faster.

Can I export to CSV or Excel? Yes. All results are in the dataset and can be downloaded as JSON, CSV or Excel or pulled via API.