seaworld008/grype-syft-sbom-scanner

Grype + Syft SBOM Scanner

Trigger / When to Use

Use this skill when the user wants SBOM-first vulnerability management, container image scanning, package inventory, or repeatable vulnerability scans using Anchore open-source tools Syft and Grype.

Good trigger phrases:

• "generate an SBOM and scan it"
• "scan this container with Grype"
• "compare vulnerabilities between two images"
• "produce CycloneDX or SPDX"
• "scan a directory or archive for CVEs"
• "make vulnerability results reproducible from SBOM"

Core Capabilities

• Generate SBOMs from container images, directories, files, archives, and package metadata with Syft.
• Scan container images, directories, SBOMs, and individual package identifiers with Grype.
• Separate inventory generation from vulnerability matching for repeatable audits.
• Compare scan results over time as vulnerability databases change.
• Integrate SBOM and vulnerability outputs into CI/CD and release evidence.
• Support SPDX, CycloneDX, and Syft JSON workflows.

Workflow

1. Pick the SBOM Strategy

Use one of these modes:

• Direct Grype scan for quick triage.
• Syft SBOM plus Grype scan for reproducibility.
• Stored SBOM scan for release, compliance, or incident response.

Prefer SBOM-first when the result will be attached to a release, shared with customers, or compared later.

2. Verify Tools

syft version
grype version

If missing, install from official Anchore channels. Pin versions in CI when release evidence matters.

3. Generate an SBOM

For a container image:

syft registry.example.com/app:1.2.3 -o cyclonedx-json=sbom.cdx.json

For a local source or filesystem directory:

syft dir:. -o spdx-json=sbom.spdx.json

For Syft JSON:

syft packages . -o syft-json=sbom.syft.json

4. Scan with Grype

Scan an image directly:

grype registry.example.com/app:1.2.3

Scan a directory:

grype dir:.

Scan an SBOM:

grype sbom:sbom.cdx.json

Fail on high-severity findings in CI:

grype registry.example.com/app:1.2.3 --fail-on high

5. Produce Reports

grype sbom:sbom.cdx.json -o json > grype-results.json
grype sbom:sbom.cdx.json -o sarif > grype-results.sarif
grype sbom:sbom.cdx.json -o table

Retain:

• SBOM file.
• Scanner version.
• Vulnerability DB update timestamp.
• Image digest or git commit.
• Grype output.

6. Triage Findings

For each finding, capture:

• Vulnerability ID.
• Package name, version, type, and location.
• Match type and confidence.
• Fixed version.
• Image layer or file path when available.
• Whether the package is runtime, build-only, or unused.

Prioritize runtime packages over build-only layers unless the build system is also in scope.

Common Patterns

Release Evidence Bundle

release-security/
  image-digest.txt
  sbom.cdx.json
  grype-results.json
  grype-results.sarif
  scanner-versions.txt
  accepted-risk.md

GitHub Actions Example

name: sbom-vuln-scan
on: [pull_request]
jobs:
  scan:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Generate SBOM
        run: syft dir:. -o cyclonedx-json=sbom.cdx.json
      - name: Scan SBOM
        run: grype sbom:sbom.cdx.json --fail-on high

Image Comparison

syft old-image:tag -o syft-json=old.sbom.json
syft new-image:tag -o syft-json=new.sbom.json
grype sbom:old.sbom.json -o json > old.vulns.json
grype sbom:new.sbom.json -o json > new.vulns.json

Summarize deltas by new, fixed, unchanged, and severity-changed vulnerabilities.

Interpretation Rules

• An SBOM is an inventory, not a security verdict.
• A vulnerability match can depend on package metadata quality.
• Distro vendor advisories can disagree with NVD severity or fix status.
• Image scans should use immutable digests for release evidence.
• Re-scanning old SBOMs can show newly disclosed vulnerabilities without rebuilding artifacts.

Boundaries

• Do not assume Grype and Trivy will produce identical results.
• Do not delete packages blindly from images without checking runtime dependencies.
• Do not publish SBOMs externally without approval; SBOMs reveal technology inventory.
• Do not treat a missing fixed version as an automatic blocker without risk analysis.
• Do not use SBOM-only results as proof that source code has no custom vulnerabilities.

Reference Sources

• Anchore OSS docs: https://oss.anchore.com/docs/
• Grype scan targets: https://oss.anchore.com/docs/guides/vulnerability/scan-targets/
• Syft scan targets: https://oss.anchore.com/docs/guides/sbom/scan-targets/