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Mirrornvd

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Mirroring External Resources

If an organization blocks the servers performing dependency-check scans from downloading content on the internet they may need to mirror multiple data sources as documented at Remote Data Sources, however access to data from the NVD API is currently mandatory.

Mirrors are made available by setting a special URL template in the nvdDatafeed/nvdDatafeedUrl configuration. Configuring this URL switches NVD updates from the REST API to data feeds in the NVD JSON 2.0 schema format. The {0} placeholder is replaced with a year or modified when dependency-check retrieves feed data.

Switching to data feeds from the API has some advantages and disadvantages you should consider:

  • ✅ reliability: insulates from API-specific rate limits and availability issues
  • ✅ reliability: can be safely cached and proxied via a private centralized forward proxy
  • ❌ performance: increases data and CPU usage. The entire feed file is downloaded for each update and every entry in the dependency-check database is updated
  • ❌ support: most options lack a documented SLA
  • ❌ complexity: relies on the data feed correctly reflecting all NVD API data changes, depending on additional tools or NVD's own proprietary feed creation process

Consult your specific dependency-check integration's documentation for configuration details.

Using dependency-check's own 2.0 data feed mirror

Dependency-check maintains its own mirror/cache, built directly from the NVD API using the vulnz CLI.

If using the dependency-check CLI, set the NVD Datafeed URL to the feed filename pattern:

shell
dependency-check.sh --nvdDatafeed \
    'https://dependency-check.github.io/DependencyCheck_Builder/nvd_cache/nvdcve-{0}.json.gz'

This is updated every 24 hours on a best-effort basis. When the NVD API is unavailable, it will contain stale data.

Using the NVD 2.0 data feeds

Dependency-check can use the official NVD 2.0 JSON data feeds instead of the NVD REST API.

If using the dependency-check CLI, set the NVD Datafeed URL to the feed filename pattern:

shell
dependency-check.sh --nvdDatafeed \
    'https://nvd.nist.gov/feeds/json/cve/2.0/nvdcve-2.0-{0}.json.gz'

The official NVD 2.0 data feeds have sometimes been stale for extended periods (one to two weeks), and during high-load periods can be aggressively rate-limited. This can lead to extremely slow download speeds, frequent timeouts, and interrupted downloads. Consider using a caching forward proxy between dependency-check and the NVD to improve reliability.

Creating an offline cache for the NVD API

The Open Vulnerability Project's vuln CLI can be used to create an offline copy of the data obtained from the NVD API. Then configure dependency-check to use the NVD Datafeed URL.