masscan_scan · Kali MCP Server MCP: Risk & Policy

WHAT IT DOES

What masscan_scan does on Kali MCP Server

AI agents invoke masscan_scan to trigger actions in Kali 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 masscan_scan needs a policy

masscan actively probes network targets by sending TCP/UDP packets at high speed, constituting an external operation with side effects on target systems. It is not a passive read operation. While it doesn't modify or delete data, it executes network reconnaissance against potentially remote hosts. Misuse could constitute unauthorized scanning of third-party infrastructure, hence high severity.

From the tool's definition 'Perform fast masscan port scan' - masscan is an active network scanning tool that sends packets to external hosts, triggering real network operations against target systems

Risk signalsBulk/mass operation — affects multiple targets

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

masscan_scan Rate-limited

masscan_scan 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": {
    "masscan_scan": {
      "limits": [
        {
          "counter": "masscan_scan_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 Kali MCP Server, so you can run agents against it safely.

FAQ

Questions about masscan_scan

What does the masscan_scan tool do? +

Perform fast masscan port scan. It is categorised as a Execute tool in the Kali 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 masscan_scan? +

Register the Kali MCP Server MCP server in PolicyLayer and add a rule for masscan_scan: 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 Kali MCP Server. Nothing to install.

What risk level is masscan_scan? +

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

Can I rate-limit masscan_scan? +

Yes. Add a rate_limit block to the masscan_scan 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 masscan_scan completely? +

Set action: deny in the PolicyLayer policy for masscan_scan. 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 masscan_scan? +

masscan_scan is provided by the Kali MCP Server MCP server (jesseeikeland/kali-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.