Passive external attack-surface mapping: CT subdomains, DNS, TLS, HTTP posture, RDAP/WHOIS, Shodan.
To add attack-surface-mcp-server to Claude, run the install command below or copy the ready-made config for Claude Code, Claude Desktop, Cursor and VS Code further down. Restart your client after adding it and its tools show up in your next conversation. It needs 8 environment variables, listed below.
Install
npx -y @cyanheads/attack-surface-mcp-server@0.5.0Environment variables
SHODAN_API_KEYSet in your MCP configCERTSPOTTER_API_KEYSet in your MCP configATTACKSURFACE_DEFAULT_RESOLVERSSet in your MCP configATTACKSURFACE_HTTP_USER_AGENTSet in your MCP configATTACKSURFACE_MAX_SUBDOMAINSSet in your MCP configATTACKSURFACE_RDAP_BOOTSTRAP_URLSet in your MCP configATTACKSURFACE_ALLOW_PRIVATE_TARGETSSet in your MCP configMCP_LOG_LEVELSet in your MCP configInstall with your client
claude mcp add attack-surface --env SHODAN_API_KEY=<YOUR_SHODAN_API_KEY> --env CERTSPOTTER_API_KEY=<YOUR_CERTSPOTTER_API_KEY> --env ATTACKSURFACE_DEFAULT_RESOLVERS=<YOUR_ATTACKSURFACE_DEFAULT_RESOLVERS> --env ATTACKSURFACE_HTTP_USER_AGENT=<YOUR_ATTACKSURFACE_HTTP_USER_AGENT> --env ATTACKSURFACE_MAX_SUBDOMAINS=<YOUR_ATTACKSURFACE_MAX_SUBDOMAINS> --env ATTACKSURFACE_RDAP_BOOTSTRAP_URL=<YOUR_ATTACKSURFACE_RDAP_BOOTSTRAP_URL> --env ATTACKSURFACE_ALLOW_PRIVATE_TARGETS=<YOUR_ATTACKSURFACE_ALLOW_PRIVATE_TARGETS> --env MCP_LOG_LEVEL=<YOUR_MCP_LOG_LEVEL> -- npx -y @cyanheads/attack-surface-mcp-server@0.5.0
Run this in a terminal to add the server to Claude Code.
What this does
attack-surface-mcp-server exposes a set of tools to Claude over the Model Context Protocol. After you add it to claude_desktop_config.json (snippet above) and restart Claude Desktop, those tools become callable inside any conversation.
Requirements
This server needs the following environment variables to be set before it can run:
SHODAN_API_KEY CERTSPOTTER_API_KEY ATTACKSURFACE_DEFAULT_RESOLVERS ATTACKSURFACE_HTTP_USER_AGENT ATTACKSURFACE_MAX_SUBDOMAINS ATTACKSURFACE_RDAP_BOOTSTRAP_URL ATTACKSURFACE_ALLOW_PRIVATE_TARGETS MCP_LOG_LEVEL
Set these via the env object in your MCP config (see claude_desktop_config.json snippet above).
Frequently asked questions
How do I install attack-surface-mcp-server?
Run the Claude Code command in the install section to add attack-surface-mcp-server to Claude Code, or copy the ready-made config for your client from the install section on this page. Restart your client afterwards and the tools appear in your next conversation.
Which clients work with attack-surface-mcp-server?
This page carries setup and config for Claude Code, Claude Desktop, Cursor and VS Code. Any other MCP client that accepts a standard server config can connect to attack-surface-mcp-server as well.
Does attack-surface-mcp-server need an API key?
Yes. Before it can run, set these environment variables: SHODAN_API_KEY, CERTSPOTTER_API_KEY, ATTACKSURFACE_DEFAULT_RESOLVERS, ATTACKSURFACE_HTTP_USER_AGENT, ATTACKSURFACE_MAX_SUBDOMAINS, ATTACKSURFACE_RDAP_BOOTSTRAP_URL, ATTACKSURFACE_ALLOW_PRIVATE_TARGETS, MCP_LOG_LEVEL. They go in the env block of your MCP config.
Imported from the Official MCP Registry. The details above come from the registry entry; the maker can claim this listing to correct them, add docs, and see its traffic.
Is this your MCP server?
Claim this listing to see its traffic, fix details yourself, and skip the review queue on future updates.
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