Best MCP Security and Scanning Tools in 2026

The best MCP security tools fall into three groups. Scanners check a server's tools and code before you connect it. Runtime guards sit between your AI app and the server and block bad changes or data. Red-team tools attack your setup on purpose to find weak spots.

MCP (Model Context Protocol) lets AI apps like Claude or ChatGPT call outside tools. That power brings new risks. A server's tool description can hide instructions for the AI, a trick called tool poisoning. A server can also change its behavior after you approve it, which is called a rug pull.

We reviewed nine tools against their own repos and docs on 28 October 2026. We did not run these tools on client systems for this article. Every claim is attributed to the vendor and linked.

How we chose

We included a tool only if it passed three tests:

1. Live and public. We could open its repo or docs on 28 October 2026.
2. MCP-specific. It names MCP servers, tools or configs as something it scans, guards or tests.
3. Clear cost and data handling. It publishes a license or pricing, and we could see whether it calls an outside API.

We left out general AI firewalls that did not document MCP features on a page we could open. Gateways with security add-ons are covered more fully in our MCP gateways list.

Comparison table

1. Snyk Agent Scan: broad scanner for agents, MCP servers and skills

What it is. Snyk Agent Scan is a "security scanner for AI agents, MCP servers and agent skills." The old Invariant Labs mcp-scan repo address now opens this Snyk repo; Snyk announced it had acquired Invariant Labs in June 2025 (see our Invariant Labs spotlight). Snyk says version 0.6 and later checks 14 risks, including prompt injection, destructive capabilities, suspicious downloads, malicious code and secret handling.

You run it with uvx snyk-agent-scan@latest, and it needs a Snyk API token. Snyk says the tool sends "agent application details, MCP server configurations and signatures, tool names and descriptions, and skill content" to its API, with secrets redacted first. It also says it "does not store or log" the contents and results of your tool calls.

Best for: Developer and security teams who want one scanner across Claude, Cursor and other agent configs on a laptop.

Pricing: The CLI is free and open source (Apache-2.0). You need a Snyk account token. Snyk's plans page lists a Free plan at $0 and says Evo features, which Agent Scan's background mode reports to, are not on Free or Team plans.

Pros

• Wide coverage of MCP and agent skill risks.
• One tool covers agents, MCP servers and agent skills.
• Secrets are redacted before data is sent.

Cons

• Tool descriptions and configs go to Snyk's API, which some companies will need to review.
• Scans can launch stdio servers, so Snyk advises a sandbox for untrusted configs.

Checked against: Snyk Agent Scan on GitHub on 28 October 2026.

2. Cisco MCP Scanner: three detection engines in one CLI

What it is. Cisco's MCP Scanner "combines Cisco AI Defense inspect API, YARA rules and LLM-based analysis to detect malicious MCP tools." YARA is a widely used pattern-matching format for finding malware. Cisco says you can use the engines together or one at a time.

It can scan "MCP tools, prompts, resources, and server instructions," plus the source code of MCP servers, Python and npm packages, and dependencies. Offline readiness and prompt-defense checks need no API key.

Best for: Security teams that want to choose how much leaves the building, from fully offline rules to cloud analysis.

Pricing: Free and open source (Apache-2.0). The Cisco AI Defense engine needs an AI Defense API key. The LLM engine needs your own LLM provider key, and VirusTotal checks need a VirusTotal key.

Pros

• Works offline with rule-based checks.
• Scans server source code, not just tool descriptions.
• Install with one uv tool install command.

Cons

• The strongest engine depends on a separate Cisco AI Defense key.
• Requires Python 3.11 or newer and uv, which non-developers may not have.

Checked against: Cisco MCP Scanner on GitHub on 28 October 2026.

3. Trail of Bits mcp-context-protector: a wrapper that stops rug pulls

What it is. mcp-context-protector is "a security wrapper for MCP servers that addresses risks associated with running untrusted MCP servers." It sits between your AI app and the server, so it works with any MCP client.

Its main feature is "trust-on-first-use pinning." You approve a server's instructions, tool descriptions and inputs once. If any of them change, the wrapper blocks tool calls until you approve again. It can also quarantine flagged tool responses and strip ANSI control characters, which are hidden terminal codes that can disguise text.

Best for: Teams using third-party servers that update often, where a silent change is the main worry.

Pricing: Free and open source (Apache-2.0).

Pros

• Directly addresses rug pulls by blocking unapproved changes.
• Works with any MCP host app.
• Quarantines flagged tool responses for later review.

Cons

• Adds an approval step every time a server legitimately updates.
• No maturity or release status is stated in the README.

Checked against: mcp-context-protector on GitHub on 28 October 2026.

4. Docker MCP Gateway: container isolation for every server

What it is. Docker's docs say MCP Gateway "runs MCP servers in isolated Docker containers with restricted privileges, network access, and resource usage." It injects credentials, so keys are not scattered across config files, and it has "built-in logging and call-tracing capabilities."

The gateway's GitHub repo says the CLI plugin is already installed on recent Docker Desktop versions. Docker says it builds and signs the local servers in its catalog.

Best for: IT teams who want each server boxed in, so a bad server cannot read the whole laptop.

Pricing: The gateway is open source (MIT). Docker's docs describe the related Docker AI Governance feature as "invite-only" and point you to Docker Sales.

Pros

• Container isolation limits what any one server can reach.
• Central credential handling and call logs.
• Pairs with the signed servers in the Docker MCP Catalog.

Cons

• Requires Docker, which adds setup for non-technical staff.
• Isolation limits damage but does not detect a poisoned tool description by itself.

Checked against: Docker MCP Gateway docs on 28 October 2026.

5. Lasso MCP Gateway: filters secrets and PII in tool traffic

What it is. Lasso's MCP Gateway is "a plugin-based gateway that orchestrates other MCPs." Plugins mask data as it passes through. The basic plugin masks tokens such as GitHub, AWS and Slack keys. The presidio plugin masks personal data like emails, phone numbers, card numbers and SSNs.

Its --scan option "analyzes server reputation and security risks before loading MCP servers." Lasso's README says it uses marketplace data from Smithery and npm, plus GitHub data, and blocks servers below a reputation threshold. Smithery says its API stops working on 31 October 2026 (Smithery's notice), and Lasso's README had not been updated for that as of 28 October 2026, so check how the scanner behaves after that date.

Best for: Teams worried about AI tools leaking customer data or secrets through tool calls.

Pricing: Free and open source (MIT). The optional lasso plugin uses Lasso's own API.

Pros

• Masks secrets and personal data in both requests and responses.
• Reputation check before a server loads.
• Published on PyPI for easy install.

Cons

• A small project (about 400 GitHub stars on 28 October 2026).
• No release version or maintenance status shown on the repo page.

Checked against: Lasso MCP Gateway on GitHub on 28 October 2026.

6. Promptfoo: red-team testing for MCP-connected apps

What it is. Promptfoo is a CLI for "red teaming/pentesting/vulnerability scanning for AI." Its repo says "Promptfoo is now part of OpenAI" and "remains open source and MIT licensed."

Its MCP plugin tests for "function call exploits, system prompt leakage, unauthorized tool discovery," and other MCP attacks. The MCP testing guide covers tool poisoning, tool shadowing, rug pulls and data exfiltration.

Best for: Teams that build their own AI agent or MCP server and want to attack it before customers do.

Pricing: The pricing page lists a free Community plan with red teaming up to 10,000 probes a month. Enterprise and On-Premise plans are custom priced.

Pros

• Tests real behavior, not just static descriptions.
• Covers multi-server risks like shadowing and rug pulls.
• Free tier with a generous probe allowance.

Cons

• Needs a test setup and config file, so it suits developers.
• Results depend on how well you describe your app's purpose.

Checked against: Promptfoo MCP security testing guide on 28 October 2026.

7. Ramparts (Highflame): scanner built for CI pipelines

What it is. Ramparts is an "MCP & SKILL scanner that scans any mcp server or skills for indirect attack vectors." It uses YARA rules and LLM analysis. It checks OSV.dev for known vulnerabilities in npx and uvx servers, and flags drift against a saved baseline.

Findings map to the OWASP MCP Top 10. Output formats include JSON and SARIF, a standard format that GitHub and other CI tools can read.

Best for: Engineering teams that want MCP checks to run in their build pipeline.

Pricing: Free and open source (Apache-2.0).

Pros

• SARIF output fits existing code-scanning dashboards.
• Drift detection catches changed tool definitions.
• OWASP mapping helps with audit reports.

Cons

• The README warns it is "under active development" and "inaccuracies are inevitable."
• Installs through Rust's cargo, which many teams do not use.

Checked against: Ramparts on GitHub on 28 October 2026.

8. MCP-Shield: a fast first look at installed servers

What it is. MCP-Shield "scans your installed MCP servers." It looks for hidden instructions in tool descriptions, possible data exfiltration channels, tool shadowing, attempts to read sensitive files, and cross-server conflicts. You run it with npx mcp-shield. Adding an Anthropic Claude API key turns on AI-assisted analysis.

Best for: A solo developer or consultant who wants a quick check of a laptop's MCP setup.

Pricing: Free and open source (MIT).

Pros

• No install step beyond Node.js.
• Covers the classic MCP attack patterns.
• Optional AI analysis with your own key.

Cons

• A small project with few commits, so updates may be slow.
• Local scan only, with no runtime protection.

Checked against: MCP-Shield on GitHub on 28 October 2026.

9. Nova Proximity: scanner with custom rules

What it is. Nova Proximity "scans MCP servers and Agent Skills to discover tools, prompts, and resources." It reads tool annotations such as read-only and destructive flags. Security checks run through NOVA, a rule engine that combines keywords, semantic matching and LLM checks. The README credits Thomas Roccia as the author.

Best for: Security analysts who want to write their own detection rules.

Pricing: Free and open source (GPL-3.0).

Pros

• Custom rules let you encode your own policies.
• Supports Streamable HTTP servers.
• Inventories tools, prompts and resources in one view.

Cons

• GPL-3.0 license may limit how companies bundle it.
• Writing good rules takes security skill.

Checked against: Nova Proximity on GitHub on 28 October 2026.

How to combine these tools

Think in layers, not a single purchase.

1. Before you connect: Run a scanner such as Snyk Agent Scan, Cisco MCP Scanner or Ramparts on new servers.
2. While it runs: Use a guard such as mcp-context-protector, Docker MCP Gateway or Lasso's gateway.
3. Before you ship your own server: Red-team it with Promptfoo.
4. Always: Grant the smallest permissions possible. Many official servers support it. Supabase, Linear and GitHub all offer read-only modes, as covered in our developer servers list.

Tools are only part of the answer. Our explainer on whether MCP is safe covers the business decisions, and MCP governance for IT leaders covers logging and access policy. If you want an outside review, eSEOspace runs an MCP readiness audit.

Next step

Scanners only help if you know what they are looking for. Read MCP Security Risks and How to Reduce Them next, or return to the MCP Guide.

Frequently asked questions