Free passive scan

Free Server Information Disclosure Checker

Free tool

Detect Server and X-Powered-By headers that leak your stack and versions to attackers, with copy-paste fixes for Nginx, Apache, Express, and Next.js.

  • Server header leaks
  • X-Powered-By
  • Version exposure
No credit card requiredRead-only, no exploitationNo setup or code required
Used by 5,000+ developers and engineering teams
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What you get for free

18 core security checks via this tool, passive scans, step-by-step remediation, security score on every result.

What Essential adds from €199/mo

Pentest credits every month, +17 advanced checks, weekly passive scans, email alerts and audit-ready PDFs for SOC 2 / ISO 27001 / PCI.

Examples (good vs bad)

Bad: Server: nginx/1.16.1, X-Powered-By: Express

Better: Server: cloud, no X-Powered-By

What is server info disclosure?

HTTP headers like Server and X-Powered-By can reveal software and version details. Attackers use these to target known vulnerabilities.

How to minimize exposure

  • Strip or generalize Server/X-Powered-By
  • Avoid leaking framework versions
  • Harden error pages and stack traces

Across 7,440 recent scans, 70.1% leak Server / X-Powered-By headers that reveal stack details to attackers.

Implementation examples

Once you've identified the gap, applying the fix is straightforward. Here are the configurations developers reach for most often.

Nginx

# nginx.conf
# Hides the version, leaving just "Server: nginx"
server_tokens off;

# Clearing headers entirely needs the headers-more module
# (nginx-module-headers-more on most distros)
more_clear_headers 'Server' 'X-Powered-By';

Apache

# httpd.conf
# Reduces the Server header to just "Apache" - stock Apache
# cannot remove it completely without ModSecurity or a proxy
ServerTokens Prod
ServerSignature Off
Header unset X-Powered-By

Node.js (Express)

import express from "express"

const app = express()
// Removes the X-Powered-By: Express header
app.disable("x-powered-by")

Next.js (next.config.mjs, works on Vercel)

const nextConfig = {
  poweredByHeader: false,
}

export default nextConfig

This removes the X-Powered-By header. The Server header itself is added by the platform or proxy in front of your app, so it is controlled there.

Tool-specific questions

Is hiding versions security by obscurity?

It reduces attacker reconnaissance. Combine with patching and WAF rules for layered defense.

Can CDNs override these headers?

Yes - configure your CDN/edge to remove or standardize them.
Why Barrion

Built for the engineers who already have enough to fix.

Speed

Fast results

Instant analysis with a detailed report. You see findings as the scan runs, not after.
Coverage

Comprehensive checks

The full passive scan runs 18 checks on the free plan, covering TLS, headers and cookies. Paid plans run 35+ and add CORS, DNS, email auth and more.
Action

Step-by-step fixes

Every finding ships with the exact remediation step for your framework. Hand it to the engineer who owns the surface.
FAQ

Frequently asked.

What is Barrion?
Barrion runs continuous, agentic AI penetration tests of web applications and APIs. AI agents test your app the way an attacker would, safely, on a schedule or on demand. Findings are checked against the live app before they're reported, and tracked across runs as new, still open, resolved or regressed. From Standard level up, a security engineer reviews each report. Barrion AB is based in Gothenburg, Sweden. A free passive scan is the quickest way to start.
How safe is Barrion to use for security testing?
AI pentests send real test requests, so they're rate-limited and non-destructive, and you approve the exact scope before a single request goes out. You can point them at staging too. The free passive scan only reads your live app. It never submits forms, brute-forces endpoints or touches anything that changes state, so it's safe to run against production.
What types of security issues does Barrion identify?
AI pentests look for the issues an attacker could exploit, like SQL injection, cross-site scripting and broken access control. Findings are checked against your live app, and confirmed ones come with the request and response that prove them. Anything we couldn't confirm is clearly marked and capped in severity. The passive scan catches misconfigurations in TLS and HTTPS, security headers, cookie flags, CORS policy, DNS records, email authentication (SPF, DKIM, DMARC) and network exposure.
What specific security checks does Barrion perform?
Barrion covers two surfaces. AI pentesting is the active part: specialist agents chain requests to find exploitable flaws such as SQL injection, cross-site scripting and broken access control. Findings are checked against your live app, and confirmed ones come with the request and response that prove them. The passive scan is read-only and safe to point at production. On paid plans it runs 35+ checks (18 on the free plan): transport security (HTTPS, HSTS, TLS version, cipher suites, certificate expiry, hostname and chain validity, OCSP stapling), HTTP response headers (Referrer-Policy, Permissions-Policy, X-Content-Type-Options, Content-Type, server information disclosure), CSP and framing (Content-Security-Policy, bypass detection, Trusted Types, X-Frame-Options), cross-origin policy (COOP, COEP, CORP and the full CORS header set), cookie flags and anti-CSRF tokens, mixed content, vulnerable JavaScript libraries, DNS records including DNSSEC and CAA, email authentication (SPF, DKIM, DMARC), open ports and subdomain takeover. Findings from both are ranked by severity and come with step-by-step remediation.
Will our auditor or enterprise customer accept the report?
The report maps every finding to OWASP WSTG, a security engineer reviews it from Standard up and signs it off from Deep up, and a free retest shows what you fixed. Teams use it as evidence for SOC 2, ISO 27001 and NIS2 work. Whether it's accepted is up to your auditor.
How often does Barrion test my app?
Continuously or on demand. On the Business plan you save a pentest and it reruns daily, weekly, monthly, quarterly, every six months, yearly or on your own rhythm. On any plan you can start a pentest or a passive scan on demand. A passive scan also runs on a schedule and alerts you when something new shows up.
Is Barrion suitable for security testing of all business sizes?
Yes. Solo developers often start with the free passive scan and a single pentest. Teams with several apps run pentests on a schedule, and it fits alongside the tools you already run.
How does Barrion handle data security and privacy during security testing?
Passive scans are read-only: they only look at what your app already exposes publicly. For AI pentests we store the findings and the evidence behind them, the requests and responses that confirm each issue, so you can review and reproduce them. Test credentials you add are encrypted. Data is stored and hosted in Sweden and AI processing runs in the EU. Our trust page lists every subprocessor. Pentests are rate-limited and only run inside the scope you approve.
What if I'm not satisfied with Barrion's security testing service?
You can cancel anytime in the dashboard, and paid plans carry a 14-day refund window from the first charge. If something isn't right, contact us and we'll make it work for your team.
How does Barrion help with SOC 2, ISO 27001, NIS2, and other compliance frameworks?
Barrion's pentest reports come as PDF, XLSX and JSON, mapped to all 97 OWASP WSTG test cases, with engineer review from Standard up, sign-off from Deep up and a free retest after fixes. Teams use them as evidence that supports SOC 2, ISO 27001, PCI DSS and NIS2 work. Whether a report is accepted is up to your auditor or customer.

Anything else? Email contact@barrion.io.

A scan shows the surface. A pentest tests what gets in.

Passive scan

  • Reads what your app already exposes
  • Never logs in or submits a form
  • Cannot confirm what is exploitable

Active AI pentest

  • Tests your app the way an attacker would
  • Chains requests to confirm real exploits
  • Replays findings against your live app
  • Runs on a schedule or on demand, retests free

Probes for

  • SQL injection
  • Broken access control
  • IDOR
  • SSRF
  • Business-logic abuse

How AI pentesting works

Paid in credits. Free retests of found issues, and expert review from Standard up.