openvas_scan · Kali MCP: Risk & Policy

WHAT IT DOES

What openvas_scan does on Kali

AI agents invoke openvas_scan to trigger actions in Kali. 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 openvas_scan needs a policy

OpenVAS is an active vulnerability scanner that sends probes and exploits test cases against target hosts. This constitutes execution of external operations whose effects depend on the arguments (target host/network). It can cause disruption to target systems and constitutes unauthorized scanning if misused.

From the tool's definition Execute OpenVAS vulnerability scanner — actively scans target systems for vulnerabilities, triggering external network operations against potentially unauthorized targets

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

openvas_scan Rate-limited

openvas_scan 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": {
    "openvas_scan": {
      "limits": [
        {
          "counter": "openvas_scan_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 Kali, so you can run agents against it safely.

FAQ

Questions about openvas_scan

What does the openvas_scan tool do? +

Execute OpenVAS vulnerability scanner. It is categorised as a Execute tool in the Kali MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on openvas_scan? +

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

What risk level is openvas_scan? +

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

Can I rate-limit openvas_scan? +

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

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

openvas_scan is provided by the Kali MCP server (pentestt00ls/kali-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.