Flawfinder Integration Guide

Integrate Flawfinder with Vulnetix. Scan C and C++ code for potential security flaws and upload SARIF results.

Install & scan

$ uv run --with flawfinder flawfinder --version
$ uv run --with flawfinder flawfinder --sarif . > flawfinder.sarif

Run Flawfinder in CI

Scan on every push and upload the report as a workflow artifact:

- name: Run Flawfinder
  run: |
    pip install flawfinder
    flawfinder --sarif . > flawfinder.sarif

- name: Upload report
  uses: actions/upload-artifact@v6
  with:
    name: flawfinder
    path: flawfinder.sarif
    if-no-files-found: warn

Then one publish job hands every artifact in the run to Vulnetix, recorded under Flawfinder's own name and version. Written once per workflow, however many scanners you run:

publish:
  name: Publish to Vulnetix
  runs-on: ubuntu-latest
  needs: [scan]        # every scanner job, or its report is never published
  if: always()         # or one failing scanner suppresses all the others
  permissions:
    contents: read
    actions: read      # required to list the run's artifacts
  env:
    VULNETIX_ORG_ID: ${{ secrets.VULNETIX_ORG_ID }}
    VULNETIX_API_KEY: ${{ secrets.VULNETIX_API_KEY }}
  steps:
    - uses: actions/checkout@v5
    - name: Install Vulnetix CLI
      run: |
        curl -fsSL https://cli.vulnetix.com/install.sh | sh -s -- --install-dir "$HOME/.local/bin"
        echo "$HOME/.local/bin" >> "$GITHUB_PATH"
    - name: Publish scanner reports
      env:
        GITHUB_TOKEN: ${{ github.token }}
      run: vulnetix gha upload --org-id "$VULNETIX_ORG_ID" --json

After the run, vulnetix gha status reports what was actually recorded.

How Vulnetix compares: better together

Vulnetix does not replace Flawfinder. Keep running it. Vulnetix sits on top of Flawfinder (and every other scanner you already own) turning disconnected tool outputs into one prioritised, fixable queue.

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What Flawfinder does well

• Fast, dependency-free lexical scan of C/C++ that instantly flags dangerous function usage (strcpy, sprintf, gets, format strings, race conditions)
• Findings ranked by risk level (factoring the function and its arguments) with CWE mapping and hit-density metrics
• Simple by design and CWE-compatible, with SARIF/CSV/HTML output that slots into pipelines and legacy codebases with no build step
• Long-standing, transparent open-source tool useful as a quick first pass before deeper C/C++ analysis

Where Vulnetix adds to it: Flawfinder is a naive lexical C/C++ scanner (no data-flow, source-only). Vulnetix does not replace its C/C++ heuristics but ingests its SARIF output, deduping it into a single prioritised queue and layering exploit-intel, reachability, versioned VEX + audit, SSVC and autofix, turning raw flagged function calls into triaged, evidence-backed findings.

No migration, no rip-and-replace. Flawfinder keeps doing what it does best; Vulnetix adds the orchestration, exploit-intelligence prioritisation and remediation layer built for the way AppSec works today.

Centralise Flawfinder results in Vulnetix

Upload Flawfinder SARIF output to the Vulnetix platform to deduplicate findings, prioritise them with EPSS, CISA KEV and Coalition ESS exploit intelligence, and track remediation across every scanner in a single queue.

Flawfinder documentation ↗  ·  Source repository ↗

Wire Flawfinder into your CI/CD pipeline →