This record as markdown: /tools/abl030-pfsense-mcp/pfsense-list-users.md
What pfsense_list_users does on Pfsense
AI agents call pfsense_list_users to retrieve information from Pfsense without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Why pfsense_list_users is rated Low
The 'list' verb unambiguously signals a read-only operation that queries and returns existing data (user accounts on the pfSense firewall). No data is created, modified, deleted, or executed. Severity is medium rather than low because user account information could be sensitive in a firewall context and could inform subsequent attacks, but the read itself is not destructive or immediately harmful.
From the tool's definition Tool name 'pfsense_list_users' indicates a list/query operation that retrieves user data from pfSense. Description is empty, but the naming pattern and context of a firewall management API server clearly indicate data retrieval with no side effects.
Attacks that exploit this kind of access
The rule that runs pfsense_list_users safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Pfsense, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For pfsense_list_users, this is the rule to start with:
pfsense_list_users is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Pfsense, apply this rule, and every pfsense_list_users call is checked against it from then on.
Questions about pfsense_list_users
pfsense_list_users is a read tool on the Pfsense MCP server. It is categorised as a Read tool in the Pfsense MCP Server, which means it retrieves data without modifying state.
Register the Pfsense MCP server in PolicyLayer and add a rule for pfsense_list_users: 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.
pfsense_list_users 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 pfsense_list_users 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 pfsense_list_users. 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.
pfsense_list_users 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.
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