AI agents call nat_list_port_forwards to retrieve information from OPNSense MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
The tool performs a query/list action that retrieves data about existing port forwarding rules. There are no side effects, no code execution, no data modification, and no irreversible actions. This is a straightforward informational read operation on firewall configuration.
From the tool's definition Tool name is 'nat_list_port_forwards' and description states 'List all port forward rules' — this is a read-only query operation that retrieves existing NAT/port forwarding configuration without modifying or executing any network changes.
Documented attack patterns abuse exactly the kind of access nat_list_port_forwards gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and OPNSense MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for nat_list_port_forwards:
{
"version": "1",
"default": "deny",
"tools": {
"nat_list_port_forwards": {}
}
}nat_list_port_forwards is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
List all port forward rules. It is categorised as a Read tool in the OPNSense MCP Server MCP Server, which means it retrieves data without modifying state.
Register the OPNSense MCP Server MCP server in PolicyLayer and add a rule for nat_list_port_forwards: 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 OPNSense MCP Server. Nothing to install.
nat_list_port_forwards is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the nat_list_port_forwards 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.
Set action: deny in the PolicyLayer policy for nat_list_port_forwards. 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.
nat_list_port_forwards is provided by the OPNSense MCP Server MCP server (vespo92/opnsensemcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 196 OPNSense MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
196 OPNSense MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.