pfsense_create_user · Pfsense MCP: Risk & Policy

WHAT IT DOES

What pfsense_create_user does on Pfsense

AI agents use pfsense_create_user to create or update resources in Pfsense — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Pfsense environment.

WHY IT NEEDS A POLICY

Why pfsense_create_user needs a policy

Creating users on a firewall is a reversible Write operation (users can be deleted/modified later), but has high severity because unauthorized user creation grants access to critical firewall administration interfaces, potentially enabling full system compromise.

From the tool's definition Tool name 'pfsense_create_user' indicates creation of a user account on a pfSense firewall; sibling tools show this server creates firewall rules, NAT mappings, VPN configs, and other persistent network configurations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

pfsense_create_user Rate-limited

pfsense_create_user stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "pfsense_create_user": {
      "limits": [
        {
          "counter": "pfsense_create_user_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about pfsense_create_user

What does the pfsense_create_user tool do? +

pfsense_create_user. It is categorised as a Write tool in the Pfsense MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on pfsense_create_user? +

Register the Pfsense MCP server in PolicyLayer and add a rule for pfsense_create_user: 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 Pfsense. Nothing to install.

What risk level is pfsense_create_user? +

pfsense_create_user is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit pfsense_create_user? +

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

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

pfsense_create_user is provided by the Pfsense MCP server (abl030/pfsense-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.