Petrel

MCP Internet Scanner & Fingerprinter — find exposed MCP servers before attackers do.

petrel discover                     # passive: crt.sh + HuggingFace Spaces
petrel probe https://target.com     # fingerprint a single server
petrel scan targets.txt             # batch from file

Install

pip install cobaltosec-petrel

What it finds

Petrel probes MCP servers via their JSON-RPC handshake, extracts the full tool inventory, detects auth state, and scores risk:

• execute_bash without auth → CRITICAL
• write_file without auth → HIGH
• read_file without auth → MEDIUM

Unlike Shodan, Petrel understands MCP semantics — not just "port open" but "this server exposes shell execution with no authentication."

Discovery sources (no API key required)

• crt.sh — certificate transparency logs
• HuggingFace Spaces — public MCP server deployments

Pipeline with Corvus

petrel discover -o results.jsonl
# feed into Corvus for deep security audit

Part of the CobaltoSec ecosystem

CobaltoSec · Corvus · Kestrel