nuclei · PenTest MCP Server MCP: Risk & Policy

WHAT IT DOES

What nuclei does on PenTest MCP Server

AI agents invoke nuclei to trigger actions in PenTest MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why nuclei needs a policy

Nuclei is a well-known active vulnerability scanner that sends crafted HTTP requests and payloads to target systems to detect vulnerabilities. It executes external network operations against targets, can trigger security-sensitive interactions (e.g., SSRF probes, RCE checks, authentication bypass tests), and operates within a pentest framework explicitly designed for offensive security assessments.

From the tool's definition 'Fast vulnerability scanner with templates' running within a 'penetration testing server that integrates over 30 security tools' for 'automated vulnerability scanning'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

nuclei Rate-limited

nuclei stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "nuclei": {
      "limits": [
        {
          "counter": "nuclei_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches PenTest MCP Server, so you can run agents against it safely.

FAQ

Questions about nuclei

What does the nuclei tool do? +

Fast vulnerability scanner with templates. It is categorised as a Execute tool in the PenTest MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on nuclei? +

Register the PenTest MCP Server MCP server in PolicyLayer and add a rule for nuclei: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches PenTest MCP Server. Nothing to install.

What risk level is nuclei? +

nuclei is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit nuclei? +

Yes. Add a rate_limit block to the nuclei rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block nuclei completely? +

Set action: deny in the PolicyLayer policy for nuclei. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides nuclei? +

nuclei is provided by the PenTest MCP Server MCP server (mohitsahoo/mcptoolforwebvulnerabilities-). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.