pfsense_update_system_timezone · Pfsense MCP: Risk & Policy

WHAT IT DOES

What pfsense_update_system_timezone does on Pfsense

AI agents use pfsense_update_system_timezone 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_update_system_timezone needs a policy

This tool modifies system configuration (timezone) in a reversible manner typical of Write operations. While not destructive, changing firewall system settings could disrupt logging, alerting, or scheduled tasks if set incorrectly, warranting medium severity.

From the tool's definition Tool performs PATCH operation on /api/v2/system/timezone, which modifies system configuration. The description explicitly shows this is an update operation (PATCH HTTP method) that changes system settings.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

pfsense_update_system_timezone Rate-limited

pfsense_update_system_timezone 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_update_system_timezone": {
      "limits": [
        {
          "counter": "pfsense_update_system_timezone_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_update_system_timezone

What does the pfsense_update_system_timezone tool do? +

PATCH /api/v2/system/timezone. 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_update_system_timezone? +

Register the Pfsense MCP server in PolicyLayer and add a rule for pfsense_update_system_timezone: 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_update_system_timezone? +

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

Can I rate-limit pfsense_update_system_timezone? +

Yes. Add a rate_limit block to the pfsense_update_system_timezone 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_update_system_timezone completely? +

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

pfsense_update_system_timezone 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.