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MCP-Scan

Security scanner for MCP servers against tool poisoning attacks

MCP-Scan is a security tool that scans MCP servers for vulnerabilities including tool poisoning, prompt injection, cross-origin escalation, and rug pull attacks. Acquired by Snyk in 2026, it is the first dedicated security scanner for the MCP ecosystem. It analyzes tool descriptions, permissions, and behavior patterns to detect malicious or compromised MCP servers before they can exploit AI agents.

About MCP-Scan

As the MCP ecosystem scales to thousands of community-built servers, the attack surface for AI agents has expanded dramatically. MCP-Scan addresses this emerging threat by providing automated security analysis specifically designed for Model Context Protocol servers. The tool inspects server manifests, tool descriptions, and runtime behavior to detect several classes of attacks: tool poisoning where malicious instructions are embedded in tool descriptions to manipulate LLM behavior, prompt injection through tool outputs, cross-origin escalation where one server's tools gain unauthorized access to another server's resources, and rug pull attacks where initially benign servers are later modified to include malicious functionality.

The scanning process examines both static properties and dynamic behavior of MCP servers. Static analysis checks tool descriptions for hidden instructions, excessive permission requests, and suspicious patterns that might indicate an attempt to influence agent behavior beyond the tool's stated purpose. Dynamic analysis monitors actual tool execution to detect discrepancies between declared and actual behavior, data exfiltration attempts, and unauthorized network access. The tool produces structured security reports with severity ratings and remediation recommendations that help development teams make informed decisions about which MCP servers to trust in their agent deployments.

Invariant Labs, the company behind MCP-Scan, was acquired by Snyk in April 2026, signaling that MCP security has become a mainstream concern for the developer security industry. The acquisition brings MCP vulnerability scanning into Snyk's broader application security platform, enabling organizations to include MCP server analysis in their existing security review workflows. As an Apache-2.0 licensed CLI tool, MCP-Scan can be integrated into CI/CD pipelines to automatically scan MCP server configurations before deployment, providing a security gate for the AI agent supply chain.

Pricing & Platform Specs

Pricing Summary

100% free and open-source Model Context Protocol (MCP) security auditing and vulnerability scanner developed by Invariant Labs (Apache-2.0 License). Analyzes MCP client configurations, tool schemas, and server definitions to detect prompt injection vectors, malicious tool poisoning, cross-server shadowing, and unintended permission escalation at zero software cost.

full pricing breakdown →

Supported Platforms

CLI tool — any platform with Python

Explore categories, tags & use cases

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Side-by-Side Comparisons

MCP-Scan logo
MCP-Scan
vs
Guardrails AI logo
Guardrails AI

MCP-Scan vs Guardrails AI — MCP Server Security Scanner vs LLM Output Validation Framework

MCP-Scan detects security vulnerabilities in Model Context Protocol server configurations including prompt injection and tool poisoning risks. Guardrails AI validates and controls LLM outputs with programmable rules for format, safety, and quality enforcement. MCP-Scan wins for MCP infrastructure security while Guardrails AI wins for comprehensive output validation.

Community experience

Sources & verification

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Content verified

Verification dates are editorial checks. Routine CMS saves and automatic updatedAt timestamps do not advance them.

FAQ

What is MCP-Scan?

MCP-Scan is a security tool that scans MCP servers for vulnerabilities including tool poisoning, prompt injection, cross-origin escalation, and rug pull attacks. Acquired by Snyk in 2026, it is the first dedicated security scanner for the MCP ecosystem. It analyzes tool descriptions, permissions, and behavior patterns to detect malicious or compromised MCP servers before they can exploit AI agents.

Is MCP-Scan free?

Yes — MCP-Scan is open source and free to use. 100% free and open-source Model Context Protocol (MCP) security auditing and vulnerability scanner developed by Invariant Labs (Apache-2.0 License). Analyzes MCP client configurations, tool schemas, and server definitions to detect prompt injection vectors, malicious tool poisoning, cross-server shadowing, and unintended permission escalation at zero software cost.

Is MCP-Scan open source?

Yes — MCP-Scan is open source.

Is MCP-Scan still maintained?

Yes — MCP-Scan is active. Its listing was last verified on September 6, 2026.

What are the best MCP-Scan alternatives?

The first editor-selected MCP-Scan alternatives are garak, NeMo Guardrails, LLM Guard, and more.

How does MCP-Scan score in our review?

The published editorial review lists MCP-Scan at 90/100 overall across speed, privacy, and developer experience. Check the review's evidence status and test metadata for its verification level.