Web Exposure

An MCP server that lets an AI agent point at a live deployed URL and confirm whether sensitive files are actually being served to the public — exposed .git, .env secrets, JavaScript source maps, backup/SQL dumps, directory listing, and dotfiles — by fetching the bytes and validating the content. Other tools give you a checklist of maybes; this reports only what is genuinely reachable, with evidence.

⚡ Run it in one line, no install, no API key:

npx web-exposure-mcp        # MCP server (stdio) for your AI client
npx -p web-exposure-mcp web-exposure-scan --url https://your-site.com   # one-shot CLI

🤝 Want it done for you? Fixed-scope external-exposure audit — $99 / 24h: I verify every finding live and send a written report with the exact fixes and which credentials to rotate.

npm downloads

$ npx -p web-exposure-mcp web-exposure-scan --url https://demo.example.com
2 critical, 2 high, 1 medium — 5 CONFIRMED via anonymous fetch (39 requests)
  CRITICAL  /.git/config   valid .git served — full source history downloadable
  CRITICAL  /.env          5 env vars served — API_KEY, DATABASE_URL, JWT_SECRET…
  HIGH      /main.js.map   valid source map — 142 original sources reconstructable
  HIGH      /backup.sql    SQL dump content served
  MEDIUM    /uploads/      directory listing enabled (Index of /uploads)

Why this exists

Publicly-served .git and .env files are routinely called one of the most common high-impact findings in external attack-surface management — Acunetix, Invicti and Legba all ship dedicated detections, and live HackerOne reports for exposed .git/.env are filed continuously. June 2026 saw record leaked-credential dumps, a large share sourced from live, misconfigured servers rather than breached databases.

The MCP ecosystem already covers SSL, CORS, security-headers, SEO audits, and code/commit secret scanning (GitHub MCP, GitGuardian) — but no MCP server probes a deployed URL for publicly-served secret files. This fills that gap: your agent can audit the live edge of any deployment, the way an attacker actually sees it.

The hard part isn't requesting /.env — it's avoiding false positives. Most modern sites answer 200 OK with index.html for every unknown path (SPA catch-all). web-exposure-mcp therefore reads the bytes and fingerprints the content (e.g. .git/config must parse as a git config, .env must contain KEY=VALUE secret lines, an archive must start with the real magic bytes) — so it flags facts, not guesses.

Tools (MCP)

Tool	What it does
scan_web_exposure	Probe a live URL and return only the secret files genuinely served, with evidence. Args: url (required), only (optional check filter), timeout_ms.
list_exposure_checks	List every check id, severity and the paths it probes — feed ids into only.

What it confirms

Check id	Severity	Confirmed by
git_exposed	critical	/.git/config parses as a git config, or /.git/HEAD is a valid ref/sha
env_exposed	critical	dotenv served with ≥2 KEY=VALUE secret lines (not HTML)
source_map	high	.js.map parses as a source map with a sources[] array
backup_artifact	high	SQL-dump fingerprints, or ZIP/gzip magic bytes in the body
directory_listing	medium	the autoindex signature (Index of /…) is returned
dotfile_served	high	.htpasswd hashes, .npmrc/.netrc tokens, .aws/credentials, .ssh/id_rsa, .DS_Store, docker auth

Every check fires at most once and only when the served bytes prove it. Read-only: the scanner never writes anything to the target, follows no redirects into other hosts, and reads at most 64 KB per file (so it fingerprints a multi-GB backup without downloading it).

Add to your AI client

Claude Desktop / Cursor / any MCP client — add to your mcpServers config:

{
  "mcpServers": {
    "web-exposure": {
      "command": "npx",
      "args": ["-y", "web-exposure-mcp"]
    }
  }
}

Then ask your agent: “Scan https://staging.myapp.com for publicly exposed secret files.”

CLI usage

# Probe a live deployment
npx -p web-exposure-mcp web-exposure-scan --url https://your-site.com

# Run only specific checks
npx -p web-exposure-mcp web-exposure-scan --url https://your-site.com --only git_exposed,env_exposed

# Tighter per-request timeout
npx -p web-exposure-mcp web-exposure-scan --url https://your-site.com --timeout 8000

Output is JSON on stdout (pipe into CI) and a one-line summary on stderr.

Install (optional)

npm i -g web-exposure-mcp
web-exposure-mcp                       # start the MCP server (stdio)
web-exposure-scan --url https://site.com   # one-shot scan

Zero dependencies, pure Node ≥18. Every request goes straight from the tool to the target you name — nothing leaves your machine.

Sister tools

Same active-probe philosophy — confirm the real issue by fetching it, not by trusting a checklist. All MIT:

supabase-security · strapi-security · pocketbase-security · firebase-security · appwrite-security · nhost-security

License

MIT © Renzo Madueno

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📚 Part of Awesome Backend Security Auditors — the full collection of keyless active-probe auditors.