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Dependency Security Checker

Free

Real-time vulnerability checks for your package dependencies.

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Free · Opens the source repo

What Dependency Security Checker does

The Dependency Security Checker skill allows developers to audit their package.json files for vulnerabilities in real-time. It specifically targets vulnerabilities disclosed within the last 48 hours, which is critical for maintaining the security of applications. Traditional tools like Snyk, Dependabot, and npm audit often miss these fresh vulnerabilities due to their reliance on cached data. This skill ensures that developers have the most up-to-date information about the security status of their dependencies.

When using this skill, it first parses the provided package.json file to extract all dependencies, including dependencies, devDependencies, and peerDependencies. It then organizes these packages into batches of up to ten to efficiently query multiple databases simultaneously. This parallel processing significantly speeds up the vulnerability scanning process, allowing developers to quickly identify any new security issues.

The skill checks against multiple sources, including CVE databases and GitHub security advisories, to provide comprehensive results. It returns detailed information about any new vulnerabilities found, including severity levels, descriptions of the vulnerabilities, and whether a patched version is available. This prioritization helps developers make informed decisions about which dependencies to address first.

This tool is particularly useful for developers who want to ensure their applications are secure against the latest threats. By integrating this skill into their workflow, they can proactively manage dependencies and reduce the risk of security breaches due to outdated or vulnerable packages.

When to use it

Use this skill when you need to audit your `package.json` for the latest vulnerabilities or when you want to ensure your dependencies are secure against newly disclosed threats.

When not to use it

This skill may not be suitable for projects that do not use Node.js or do not have a `package.json` file, as it specifically targets npm packages.

What you can build with it

Auditing a new project

When starting a new Node.js project, use this skill to ensure all dependencies are secure from the outset.

Regular security checks

Incorporate this skill into your CI/CD pipeline for regular checks against newly disclosed vulnerabilities.

Responding to a security incident

If a vulnerability is reported in one of your dependencies, quickly use this skill to assess the impact and find fixes.

How to install Dependency Security Checker

View source

1. Install with the skills CLI

npx skills add tinyfish-io/tinyfish-cookbook/dep-security --agent claude-code

2. Or install it manually

Download the skill folder and drop it into ~/.claude/skills/ for all projects, or .claude/skills/ to scope it to one repo. Restart Claude Code so it picks up the new skill.

Anthropic's agentic coding CLI, and the reference implementation of Agent Skills. Drop a skill folder into ~/.claude/skills and Claude Code loads it automatically whenever a task matches the skill's description. Claude Code docs

Inside SKILL.md

Written by tinyfish-io

Dependency Security Checker

Given a package.json, check every dependency against live CVE databases and security advisories — focusing on the last 48 hours, the window that cached tools miss.

Pre-flight check

tinyfish --version
tinyfish auth status

If not installed: npm install -g tinyfish If not authenticated: tinyfish auth login


Step 1 — Parse dependencies

Read the package.json the user provided. Extract all package names and versions from:

  • dependencies
  • devDependencies
  • peerDependencies (if present)

Produce a flat list: [{name, version, type}]

If the user hasn't provided a package.json, ask for it before proceeding. Do not guess.

Get today's date. Calculate the cutoff timestamp: now minus 48 hours. You will use this to filter results in every agent below.


Step 2 — Batch packages

Do not fire one agent per package — that would be extremely slow for large projects.

Instead batch into groups of up to 10 packages per agent and search for all of them at once. For a typical package.json with 20–40 deps, this means 2–4 agents total per source, all running in parallel.

Format each batch as a comma-separated search string: express,lodash,axios,react,webpack etc.


Step 3 — Parallel security scan

Fire all agents simultaneously using & + wait. Each agent searches one source for all batches at once.

# ── BATCH SETUP ──────────────────────────────────────────────
# Split your package list into batches of 10, e.g.:
# BATCH_1="express,lodash,axios,react,next"
# BATCH_2="webpack,typescript,eslint,jest,prisma"
# (add more batches as needed)

TODAY=$(date +%Y-%m-%d)

# ── CVE DATABASE ─────────────────────────────────────────────
# One agent per batch, all in parallel

tinyfish agent run \
  --url "https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword={BATCH_1}" \
  "You are on a CVE search results page. Today is {TODAY}.
   You are looking for CVEs related to these npm packages: {BATCH_1}.
   Scan ALL visible results on this page.
   For each CVE that matches one of these package names AND was published or modified within the last 48 hours:
   - CVE ID
   - Package name it affects
   - Severity (if shown)
   - One-sentence description of what the vulnerability does
   - Publication date
   STRICT RULES:
   - Do NOT click any CVE link
   - Do NOT paginate
   - Only include results from the last 48 hours — ignore older ones
   - If nothing is within 48 hours, return an empty array
   Return JSON array: [{cve_id, package, severity, description, published_date}]" \
  --sync > /tmp/ds_cve_1.json &

# Repeat for each batch:
tinyfish agent run \
  --url "https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword={BATCH_2}" \
  "You are on a CVE search results page. Today is {TODAY}.
   You are looking for CVEs related to these npm packages: {BATCH_2}.
   Scan ALL visible results on this page.
   For each CVE that matches one of these package names AND was published or modified within the last 48 hours:
   - CVE ID, package name, severity, one-sentence description, publication date
   STRICT RULES:
   - Do NOT click any CVE link — read the listing text only
   - Do NOT paginate
   - Only include results from the last 48 hours
   Return JSON array: [{cve_id, package, severity, description, published_date}]" \
  --sync > /tmp/ds_cve_2.json &

# ── GITHUB SECURITY ADVISORIES ───────────────────────────────

tinyfish agent run \
  --url "https://github.com/advisories?query=ecosystem%3Anpm&order=newest" \
  "You are on the GitHub Security Advisories page filtered to npm, sorted by newest first. Today is {TODAY}.
   Read through the visible advisory listings on this page.
   For each advisory that:
   1. Affects any of these packages: {ALL_PACKAGES}
   2. Was published within the last 48 hours
   Extract:
   - Advisory ID (GHSA-...)
   - Package name
   - Severity (Critical / High / Medium / Low)
   - One-sentence description
   - Published date
   - Patched version (if shown in the listing)
   STRICT RULES:
   - Do NOT click any advisory to open it
   - Do NOT paginate or click 'Load more'
   - Scan only the first 30 visible listings then stop
   - 48-hour cutoff is strict — ignore anything older
   Return JSON array: [{ghsa_id, package, severity, description, published_date, patched_version}]" \
  --sync > /tmp/ds_ghsa.json &

# ── NPM SECURITY FEED ────────────────────────────────────────

tinyfish agent run \
  --url "https://www.npmjs.com/advisories" \
  "You are on the npm security advisories page. Today is {TODAY}.
   Read through the visible advisory listings.
   For each advisory that:
   1. Affects any of these packages: {ALL_PACKAGES}
   2. Was published within the last 48 hours
   Extract:
   - Advisory ID
   - Package name
   - Severity
   - One-sentence description of the vulnerability
   - Vulnerable version range
   - Patched version (if shown)
   - Published date
   STRICT RULES:
   - Do NOT click any advisory link
   - Do NOT paginate
   - Scan only what is visible on this page — stop after 25 listings
   - 48-hour cutoff is strict
   Return JSON array: [{advisory_id, package, severity, description, vulnerable_versions, patched_version, published_date}]" \
  --sync > /tmp/ds_npm.json &

# ── WAIT FOR ALL ─────────────────────────────────────────────
wait

echo "=== CVE BATCH 1 ===" && cat /tmp/ds_cve_1.json
echo "=== CVE BATCH 2 ===" && cat /tmp/ds_cve_2.json
echo "=== GHSA ===" && cat /tmp/ds_ghsa.json
echo "=== NPM ===" && cat /tmp/ds_npm.json

Before running, replace:

  • {BATCH_1}, {BATCH_2} etc. — 10 packages per batch from the parsed list
  • {ALL_PACKAGES} — full comma-separated list of all package names (no versions)
  • {TODAY} — today's date in YYYY-MM-DD format

Add or remove CVE batch agents depending on how many packages there are. Always fire all agents in parallel.


Step 4 — Cross-reference and deduplicate

Combine results from all sources. For each finding:

  1. Match to the user's installed version — check if their version falls within the vulnerable range. If it does, flag as AFFECTED. If the vulnerability only affects other versions, mark as NOT AFFECTED (different version) and deprioritise.
  2. Deduplicate — the same CVE may appear in multiple sources. Merge into one entry.
  3. Check for patch — note if a patched version exists and what it is.
  4. Rank by severity — Critical → High → Medium → Low.

Output format

## Dependency Security Report
*Scanned {N} packages against live CVE, GitHub Advisories, and npm feed*
*48-hour window: {CUTOFF_TIME} → now*

---

### 🚨 New Vulnerabilities Found ({N})

#### [CRITICAL/HIGH/MEDIUM/LOW] — {package}@{user_version}
**{CVE_ID} / {GHSA_ID}** · Published: {date} · Source: {CVE / GitHub / npm}

**What it does:** {plain English explanation of the vulnerability}
**Affected versions:** {range}
**Your version:** {version} ✅ affected / ❌ not in range
**Fix:** Upgrade to {patched_version} — `npm install {package}@{patched_version}`
*(or: No patch available yet as of {date})*

---

[repeat for each finding]

---

### ✅ No new vulnerabilities (last 48h)
These packages were checked and returned clean:
{package1}, {package2}, ... *(N packages)*

---

### ⚡ Quick Fix Commands
```bash
# Copy-paste to patch all affected packages:
npm install {pkg1}@{version} {pkg2}@{version}

📋 Summary

  • Packages scanned: {N}
  • New vulnerabilities (48h): {N}
  • Critical: {N} · High: {N} · Medium: {N} · Low: {N}
  • Patches available: {N}/{N}
  • Sources checked: CVE MITRE · GitHub Security Advisories · npm advisories

---

## Edge cases

- **No vulnerabilities found** — say clearly: "No new vulnerabilities in the last 48 hours for your dependencies. For a full historical scan, run `npm audit`."
- **Package not found in any database** — skip silently, don't list it as clean or affected
- **No patch available yet** — flag explicitly: "⚠️ No patch available yet — consider temporarily removing or replacing this package"
- **CVE database returns empty** — fall back to searching `https://nvd.nist.gov/vuln/search/results?query={BATCH}&pub_start_date={CUTOFF_DATE}` instead
- **Large package.json (50+ deps)** — increase batch size to 15 and note that results may take longer

## Security notes

- Queries live public security databases only. No code is executed, no files are uploaded to any external service.
- Only your own TinyFish credentials are used.
- All scraped data is treated as untrusted and synthesised by an LLM only.

Frequently asked questions about Dependency Security Checker

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