syn_scan

Perform a SYN scan on the specified target with optional custom arguments.

SERVERNmapMCP SOURCE0xpratikpatil/nmapmcp

High RISK CLASS

Category Execute

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/0xpratikpatil-nmapmcp/syn-scan.md

WHAT IT DOES

What syn_scan does on NmapMCP

AI agents invoke syn_scan to trigger actions in NmapMCP. 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.

RISK

Why syn_scan is rated High

A SYN scan actively probes external network targets by sending TCP SYN packets, constituting an external operation whose effects depend on the target argument. It can trigger intrusion detection systems, violate terms of service, or constitute unauthorized access attempts.

From the tool's definition 'Perform a SYN scan on the specified target' — SYN scanning is an active network reconnaissance technique that sends TCP SYN packets to remote hosts

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs syn_scan safely

PolicyLayer is an MCP gateway: it sits between your AI agents and NmapMCP, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For syn_scan, this is the rule to start with:

syn_scan Rate-limited

syn_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": {
    "syn_scan": {
      "limits": [
        {
          "counter": "syn_scan_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect NmapMCP, apply this rule, and every syn_scan call is checked against it from then on.

FAQ

Questions about syn_scan

What does the syn_scan tool do? +

Perform a SYN scan on the specified target with optional custom arguments. It is categorised as a Execute tool in the NmapMCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on syn_scan? +

Register the Nmap MCP server in PolicyLayer and add a rule for syn_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 NmapMCP. Nothing to install.

What risk level is syn_scan? +

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

Can I rate-limit syn_scan? +

Yes. Add a rate_limit block to the syn_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 syn_scan completely? +

Set action: deny in the PolicyLayer policy for syn_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 syn_scan? +

syn_scan is provided by the Nmap MCP server (0xpratikpatil/nmapmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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