Vulnerability Matching

Vulnpatch uses sophisticated algorithms to match CVEs with package derivations across ecosystems. This page explains how the matching process works.

The Challenge

CVE databases and package repositories use different naming conventions:

CVE Source	Package Name
CVE-2024-XXXX	curl
GitHub Advisory	curl/curl
OSV	libcurl4 (Debian)
Nixpkgs	curlFull, curl-minimal

Vulnpatch bridges these naming gaps to provide accurate vulnerability matches.

Matching Algorithm

Step 1: Direct Name Match

First, we try exact package name matches:

Input: "openssl"
→ Match: "openssl" (100% confidence)

Step 2: Prefix/Suffix Analysis

We check for common package naming patterns:

Input: "python3-urllib3"
→ Base package: "urllib3"
→ Ecosystem hint: "python"

Step 3: Alias Resolution

We resolve known package aliases:

Input: "libssl"
→ Alias: "openssl" (Debian naming)

Step 4: Version Correlation

We verify matches by checking version compatibility:

CVE affects: openssl < 3.0.12
Package version: 3.0.11
→ Confirmed vulnerable

Confidence Scores

Each match includes a confidence score:

Score	Meaning
high	Exact name match + version confirmed
medium	Fuzzy name match or partial version info
low	Possible match, manual verification recommended

API Response

The /api/v1/vulns/:package endpoint returns matches with confidence:

{
  "success": true,
  "data": {
    "package": "curl",
    "matches": [
      {
        "cve": "CVE-2024-0853",
        "confidence": "high",
        "affectedVersions": "< 8.5.0",
        "fixAvailable": true
      }
    ]
  }
}

Improving Match Quality

Provide Ecosystem Hints

# More precise results with ecosystem parameter
curl "https://api.vulnpatch.dev/api/v1/osv/requests?ecosystem=PyPI"

Include Version Information

# Version-aware matching
curl "https://api.vulnpatch.dev/api/v1/vulns/openssl?version=3.0.11"

False Positives

Some false positives are expected. Common causes:

1. Name collisions: Different packages with the same name in different ecosystems
2. Stale data: CVE databases may trail actual fixes
3. Transitive dependencies: Vulnerability in a dependency, not the main package

Always verify critical findings manually using the provided CVE references.