nxc_ssh · Sec Netexec MCP: Risk & Policy

WHAT IT DOES

What nxc_ssh does on Sec Netexec

AI agents invoke nxc_ssh to trigger actions in Sec Netexec. 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 nxc_ssh needs a policy

SSH command execution is a quintessential Execute action—it runs arbitrary commands on remote systems whose effects depend entirely on the commands specified. The blast radius is high because successful execution could compromise target systems, exfiltrate data, modify system state, or pivot to other infrastructure.

From the tool's definition The tool explicitly enables 'command execution' via SSH protocol, allowing AI assistants to 'execute NetExec SSH protocol commands' on remote Linux/Unix systems. NetExec is a penetration testing framework that permits arbitrary command execution.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

nxc_ssh Rate-limited

nxc_ssh 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": {
    "nxc_ssh": {
      "limits": [
        {
          "counter": "nxc_ssh_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 Sec Netexec, so you can run agents against it safely.

FAQ

Questions about nxc_ssh

What does the nxc_ssh tool do? +

Execute NetExec SSH protocol commands for Linux/Unix enumeration and command execution. It is categorised as a Execute tool in the Sec Netexec MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on nxc_ssh? +

Register the Sec Netexec MCP server in PolicyLayer and add a rule for nxc_ssh: 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 Sec Netexec. Nothing to install.

What risk level is nxc_ssh? +

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

Can I rate-limit nxc_ssh? +

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

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

nxc_ssh is provided by the Sec Netexec MCP server (schwarztim/sec-netexec-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.