johnny_attack · Kali MCP: Risk & Policy

WHAT IT DOES

What johnny_attack does on Kali

AI agents invoke johnny_attack 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 johnny_attack needs a policy

Johnny is a password cracking tool that runs brute-force or dictionary attacks against password hashes or authentication systems. This is an Execute category tool because it triggers external security operations (password cracking attempts) whose outcomes depend on user-provided arguments (target, wordlist, hash type).

From the tool's definition Tool description states 'Execute Johnny password cracker' - the verb 'Execute' combined with 'password cracker' indicates running an active attack tool that performs computational operations whose effects (password discovery, system access) depend on target…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

johnny_attack Rate-limited

johnny_attack 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": {
    "johnny_attack": {
      "limits": [
        {
          "counter": "johnny_attack_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 johnny_attack

What does the johnny_attack tool do? +

Execute Johnny password cracker. 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 johnny_attack? +

Register the Kali MCP server in PolicyLayer and add a rule for johnny_attack: 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 johnny_attack? +

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

Can I rate-limit johnny_attack? +

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

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

johnny_attack 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.