# john_crack

A execute tool on the Kali Security MCP MCP server.

Agent View of the PolicyLayer registry record for `john_crack`. HTML page: https://policylayer.com/tools/seac-25-kali-security-mcp/john-crack

## Facts

- Tool: `john_crack`
- Server: Kali Security MCP (`seac-25/kali-security-mcp`) — https://policylayer.com/tools/seac-25-kali-security-mcp.md
- Homepage: https://github.com/SeaC-25/Kali-Security-MCP
- Risk category: Execute (High risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "john_crack",
    "arguments": {}
  }
}
```

## Why john_crack is rated High

John the Ripper is a well-known password cracking utility in Kali Linux. 'john_crack' almost certainly executes password cracking operations, which involves running computationally intensive processes to break password hashes. This falls under Execute as it runs external security tools. The blast radius is critical because cracking passwords can lead to unauthorized access and compromise of systems or accounts.

From the tool's own definition: "Tool name 'john_crack' strongly implies use of John the Ripper, a password cracking tool. Server description explicitly mentions penetration testing and 193 Kali Linux security tools. Description is empty, lowering confidence slightly."

## Use case

AI agents invoke john_crack to trigger actions in Kali Security MCP. 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.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Kali Security MCP:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "john_crack": {
      "limits": [
        {
          "counter": "john_crack_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Kali Security MCP (193)

- `adaptive_cmdi_test` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-cmdi-test.md
- `adaptive_create_execution_context` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-create-execution-context.md
- `adaptive_execute_strategy` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-execute-strategy.md
- `adaptive_intelligent_orchestration` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-intelligent-orchestration.md
- `adaptive_network_penetration` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-network-penetration.md
- `adaptive_sqli_test` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-sqli-test.md
- `adaptive_web_penetration` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-web-penetration.md
- `adaptive_xss_test` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/adaptive-xss-test.md
- `add_chain_step` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/add-chain-step.md
- `agent_run` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/agent-run.md
- `aircrack_attack` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/aircrack-attack.md
- `apt_comprehensive_attack` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/apt-comprehensive-attack.md
- `apt_network_penetration` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/apt-network-penetration.md
- `apt_web_application_attack` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/apt-web-application-attack.md
- `arp_scan` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/arp-scan.md
- `auth_bypass_test` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/auth-bypass-test.md
- `authorized_comprehensive_security_assessment` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-comprehensive-security-assessment.md
- `authorized_controlled_validation` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-controlled-validation.md
- `authorized_credential_assessment` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-credential-assessment.md
- `authorized_environment_review` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-environment-review.md
- `authorized_injection_verification` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-injection-verification.md
- `authorized_network_exposure_assessment` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-network-exposure-assessment.md
- `authorized_template_validation` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-template-validation.md
- `authorized_web_application_assessment` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/authorized-web-application-assessment.md
- `auto_reverse_analyze` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/auto-reverse-analyze.md
- `bandit_scan` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/bandit-scan.md
- `bettercap_attack` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/bettercap-attack.md
- `browser_click` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/browser-click.md
- `browser_close_session` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/browser-close-session.md
- `browser_execute_js` — Execute — https://policylayer.com/tools/seac-25-kali-security-mcp/browser-execute-js.md
- …and 163 more: https://policylayer.com/tools/seac-25-kali-security-mcp.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=seac-25-kali-security-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/seac-25-kali-security-mcp