MCP Security Scanner — Is Your MCP Server Safe for AI? Scan It Free.

FreeNewScans the stateless 2026-07-28 spec

35+ checks across transport security, authentication, MCP protocol compliance, injection risks, information disclosure, security headers, and rate limiting — plus checks built for the new stateless 2026-07-28 spec. Paste a URL and get results in seconds. Once your server is hardened, test how Claude, GPT, and Gemini actually call your tools in live AI conversations.

Loading scanner...
[ ADVANCED SCAN ]OWASP MCP Top 10Sign in required

The free scan sees your front door. The advanced scan comes inside.

Everything above runs unauthenticated, so it can only judge what your server exposes to a stranger. The risks that actually cost people money — a secret leaked through a tool response, a poisoned tool description, a definition that quietly changed since you approved it — are only visible from the inside. The signed-in scanner connects with your credentials and organises every finding under the ten OWASP MCP categories.

CapabilityFree scanAdvanced scan
What it can reachThe unauthenticated surface onlyConnects with your stored credentials
Tool responsesNot read — no tools are calledRead-only tools called, responses scanned for leaked secrets and PII
Agentic checksNoneAn AI designs probes for injection, poisoning and intent subversion
Change detectionSingle point-in-time resultTool definitions pinned to a baseline — a rug pull shows as a diff
ReportingA graded checklistPer-tool matrix, findings mapped to OWASP MCP Top 10, re-runnable

[ COVERAGE ]

Two of the ten cannot be established by probing a URL — they are properties of your organisation, not of one endpoint. Those are marked, and the report never dresses a self-certified answer up as a probed one.

MCP01

Token Mismanagement & Secret Exposure

MCP02

Privilege Escalation via Scope Creep

MCP03

Tool Poisoning

MCP04

Software Supply Chain Attacks & Dependency Tampering

MCP05

Command Injection & Execution

MCP06

Intent Flow Subversion

MCP07

Insufficient Authentication & Authorization

MCP08Self-attested

Lack of Audit & Telemetry

MCP09Inventory

Shadow MCP Servers

MCP10

Context Injection & Over-Sharing

[ SCAN DEPTHS ]

01Passive

No credentials, no side effects.

Reads the unauthenticated surface only — transport, auth enforcement, and tool descriptions. No AI agent, no charge.

02AuthenticatedAI

Calls read-only tools with ordinary inputs.

Calls read-only tools and reads real responses to find leaked secrets and oversharing. With your consent an AI reviews the tool descriptions for poisoning. Ordinary inputs only — nothing adversarial is sent (uses credits).

03ActiveAI

Adversarial payloads. Verified or attested hosts only.

Sends crafted attack payloads — path traversal, shell metacharacters, SQL-shaped arguments — and runs an AI agent that designs more of the same against your read-only tools. Requires a verified host, or an explicit attestation under tight limits (uses credits).

Adversarial payloads are never sent to a server you have not proved you control. The active depth requires a verified host — by DNS TXT record or .well-known file — or an explicit written attestation under hard rate limits.

Run the full OWASP MCP Top 10 against your server

Scans are org-scoped, so findings are shared with your team. Credentials are encrypted and never returned to the browser.

Done scanning? Go further.

Connect your hardened server to AI — test how Claude, GPT & Gemini call your tools, compare models, or build a reusable agent your whole team uses daily.

✦ Free credits on sign-up · no credit card needed

Why MCP Server Security Matters in 2026

A February 2026 security scan found over 8,000 MCP servers exposed on the public internet with no authentication. Any AI agent — or malicious actor — can connect to those servers, enumerate their tools, and call them without restriction.

Palo Alto Unit 42 published research in early 2026 identifying new attack vectors specific to MCP: tool poisoning (manipulating tool descriptions to hijack agent behavior) and sampling injection. Both require an attacker to first reach your server — authentication is your first line of defense.

This free scanner checks the most critical security properties of your MCP server and gives you a prioritized list of what to fix.

What This Scanner Checks

  • HTTPS: Whether your server uses TLS. HTTP servers expose auth tokens, session data, and tool payloads in plaintext — any network observer can intercept them.
  • Authentication Required: Whether the server rejects unauthenticated requests with a 401 or 403. This is the most important check — an open server is fully accessible to anyone.
  • HTTP Strict Transport Security (HSTS): Prevents browsers from falling back to HTTP connections and protects against SSL stripping attacks.
  • X-Content-Type-Options: Prevents MIME type sniffing, which can enable cross-site scripting in some browser configurations.
  • X-Frame-Options: Blocks your server's responses from being embedded in iframes, preventing clickjacking attacks.
  • Content-Security-Policy: Restricts which resources can be loaded, providing a strong second line of defense against XSS.
  • CORS Policy: A wildcard Access-Control-Allow-Origin: * means any website can make authenticated-looking requests to your server from a visitor's browser.

How to Fix Common Issues

  1. Add HTTPS — deploy your server behind a TLS-terminating reverse proxy such as Cloudflare, Nginx, or Caddy. Cloudflare's free plan handles this with zero config.
  2. Require authentication — add a Bearer token check for internal tools (5 minutes to implement) or full OAuth 2.1 with PKCE for public-facing servers.
  3. Add HSTS — set the Strict-Transport-Security: max-age=31536000 header in your server's response or in your reverse proxy config.
  4. Restrict CORS — replace * with your specific allowed origins, e.g. https://claude.ai or your application domain.
  5. Add remaining headersX-Content-Type-Options: nosniff and X-Frame-Options: SAMEORIGIN can be added in a single middleware or proxy config block.

For step-by-step implementation with code examples, read our guide on securing MCP servers with OAuth 2.1, Bearer tokens, and Cloudflare Access.

Frequently Asked Questions

What is the MCP Security Scanner?
The MCP Security Scanner is a free browser-based tool that audits any MCP (Model Context Protocol) server for common security issues. Paste a server URL and the scanner runs 35+ checks across transport security, authentication, MCP protocol compliance, injection risks, information disclosure, CORS policy, security headers, and rate limiting, then returns a graded report (A–F) with prioritized fixes.
Is the MCP Security Scanner free?
Yes, completely free. No sign-up, no API key, no rate limit. Scan as many MCP servers as you need.
Does scanning my server expose it to risk?
The scanner is deliberately conservative, but it is not purely passive — some checks have to exercise the protocol to mean anything. It reads HTTP response headers, performs the MCP handshake, and lists tools, prompts and resources. It also calls tools in two cases: the injection and tool-risk checks, and the requestState integrity check for the 2026-07-28 spec. Tool calls are limited to tools your server annotates as readOnlyHint: true, with generated placeholder arguments — a server that annotates nothing is never called. If your server exposes a tool annotated read-only that is not, scan a staging instance first.
My server requires auth — will it fail the reachability check?
No. A 401 or 403 response is a pass for the Authentication check — that is exactly what you want. The scanner checks that authentication is enforced, not that it can connect without credentials.
What is a good security score?
Grade A (90–100) means all critical and important checks pass. The two highest-weight checks are HTTPS (25 points) and authentication (30 points) — a server passing both starts at 55 points before any headers are checked. Most production servers should target a B or above.
Can I test my MCP server's tools after scanning?
Yes — MCP Playground's server tester lets you connect to any MCP server, browse its tools, and execute them with custom parameters — all from your browser.
MCP Security Scanner — Free Online MCP Server Security Audit | MCP Playground | MCP Playground