Skip to content
Recon logo

Recon

Security reconnaissance. USE WHEN recon, reconnaissance, bug bounty, attack surface. SkillSearch('recon') for docs.

SKILL.md

Full skill instructions

Customization

Before executing, check for user customizations at: ~/​.claude/​skills/​CORE/​USER/​SKILLCUSTOMIZATIONS/​Recon/

If this directory exists, load and apply any PREFERENCES.md, configurations, or resources found there. These override default behavior. If the directory does not exist, proceed with skill defaults.

recon

Infrastructure and Network Reconnaissance

Purpose

Technical reconnaissance of network infrastructure including domains, IP addresses, netblocks, and ASNs. Combines passive intelligence gathering with authorized active scanning to map attack surfaces and identify assets.

Voice Notification

When executing a workflow, do BOTH:

  1. Send voice notification:

    curl -s -X POST http://localhost:8888/​notify \
      -H "Content-Type: application/​json" \
      -d '{"message": "Running the WORKFLOWNAME workflow from the Recon skill"}' \
      > /​dev/​null 2>&1 &
    
  2. Output text notification:

    Running the **WorkflowName** workflow from the **Recon** skill...
    

Full documentation: ~/​.claude/​skills/​CORE/​SkillNotifications.md

When to Use This Skill

Core Triggers - Use this skill when user says:

Direct Recon Requests

  • "do recon on [target]" or "run recon"
  • "perform reconnaissance on [target]" or "conduct recon"
  • "do infrastructure recon" or "network reconnaissance"
  • "basic recon", "quick recon", "simple recon"
  • "comprehensive recon", "deep recon", "full reconnaissance"
  • "recon [target]" (just recon + target)
  • "passive recon", "active recon"

Infrastructure & Network Mapping

  • "map infrastructure for [domain]" or "map network"
  • "enumerate [domain] infrastructure" or "discover assets"
  • "find subdomains of [domain]" or "enumerate subdomains"
  • "scan [target]" or "port scan [IP/​netblock]"
  • "what services are running on [IP]"
  • "investigate [IP address/​domain/​netblock]"

IP & Domain Investigation

  • "recon this IP" or "investigate this IP address"
  • "look up [IP]" or "IP lookup [address]"
  • "what is [IP]" or "who owns [IP]"
  • "domain recon" or "domain investigation"
  • "DNS recon", "DNS enumeration"
  • "WHOIS [domain/​IP]"

ASN & Netblock Research

  • "investigate [ASN]" or "research ASN"
  • "scan [CIDR range/​netblock]"
  • "find IPs in [netblock]"
  • "enumerate netblock" or "netblock scanning"

Passive vs Active Recon

  • "passive recon on [target]" (no authorization required)
  • "active scan [target]" (requires explicit authorization)
  • "safe reconnaissance" (passive only)
  • "authorized scan" (active techniques)

Use Case Indicators

  • Investigating IP addresses for ownership, location, and services
  • Mapping domain infrastructure and DNS configuration
  • Scanning netblocks or CIDR ranges for live hosts
  • Researching ASN ownership and IP allocations
  • Attack surface enumeration and network mapping
  • Called by OSINT for infrastructure mapping of entities

Relationship with Other Security Skills

OSINT → recon (Common Pattern):

  • OSINT identifies entities, companies, people (social/​public records focus)
  • Recon maps their technical infrastructure (network/​system focus)
  • Example flow: OSINT finds company → Recon maps their domains/​IPs/​infrastructure

recon → webassessment:

  • Recon identifies web applications and services
  • Web assessment tests those applications for vulnerabilities
  • Example: Recon finds subdomain api.target.com → Web assessment fuzzes/​tests it

Workflow Integration:

// OSINT skill discovers company infrastructure
const domains = await osintFindCompanyDomains("Acme Corp");

// Calls recon skill to map technical details
const infraMap = await reconDomain(domains[0]);

// Recon identifies web apps
const webApps = infraMap.subdomains.filter(s => s.hasHTTP);

// Calls web assessment for testing
await webAssessment(webApps);

Core Capabilities

Passive Reconnaissance (No Authorization Required)

  • WHOIS lookups (domain and IP)
  • DNS enumeration (A, AAAA, MX, NS, TXT, CNAME, SOA, etc.)
  • Certificate transparency searches (subdomains, certificate history)
  • IPInfo API (geolocation, ASN, organization, abuse contacts)
  • Reverse DNS lookups
  • BGP/​ASN information gathering
  • Historical DNS data
  • Public database searches

Active Reconnaissance (Requires Explicit Authorization)

  • Port scanning (naabu MCP)
  • Service detection and banner grabbing (httpx MCP)
  • Technology fingerprinting
  • Live host discovery
  • HTTP/​HTTPS probing
  • SSL/​TLS analysis

CRITICAL AUTHORIZATION REQUIREMENTS:

Active reconnaissance MUST have:

  1. Explicit user confirmation for each active scan
  2. Documented authorization (pentest engagement, bug bounty program, owned assets)
  3. Scope validation (ensure target is in-scope)
  4. Rate limiting (respectful scanning, no DoS)
  5. Session logging (record all active recon for audit trail)

Default behavior is PASSIVE ONLY. Always confirm before active techniques.

Available Workflows

1. PassiveRecon.md - Safe Reconnaissance

Non-intrusive intelligence gathering using public sources:

  • WHOIS data
  • DNS records
  • Certificate transparency
  • IPInfo lookups
  • Reverse DNS
  • No active scanning

Input: Domain, IP, or netblock Output: Passive intelligence report Authorization: None required

2. IpRecon.md - IP Address Investigation

Comprehensive IP address reconnaissance:

  • IPInfo lookup (location, ASN, org, abuse contact)
  • Reverse DNS
  • WHOIS netblock info
  • Certificate search (if IP has certs)
  • Optional: Port scan (with authorization)
  • Optional: Service detection (with authorization)

Input: Single IP address Output: IP reconnaissance report Authorization: Required for active scanning

3. DomainRecon.md - Domain Investigation

Full domain mapping and enumeration:

  • WHOIS domain registration
  • DNS records (all types)
  • Subdomain enumeration (certificate transparency)
  • Mail server configuration (MX, SPF, DMARC, DKIM)
  • IP addresses behind domain
  • Certificate analysis
  • Technology stack detection
  • Historical data

Input: Domain name Output: Domain reconnaissance report Authorization: Required for active subdomain probing

4. NetblockRecon.md - CIDR Range Scanning

Network range reconnaissance:

  • CIDR parsing and validation
  • Range size calculation
  • WHOIS netblock ownership
  • Optional: Live host discovery (with authorization)
  • Optional: Port scan range (with authorization)
  • ASN/​organization mapping
  • Interesting host identification

Input: CIDR notation (e.g., 192.168.1.0/​24) Output: Netblock scan report Authorization: Required for active scanning

5. AsnRecon.md - Autonomous System Investigation

ASN and BGP reconnaissance:

  • ASN to CIDR range mapping
  • Organization information
  • All IP ranges owned by ASN
  • BGP peer relationships
  • Geographic distribution
  • Hosting/​ISP identification

Input: ASN number (e.g., AS15169) Output: ASN mapping report Authorization: None required (passive data)

Tool Integration

Primary Tools

IPInfo API (ipinfo.io)

  • API Key: process.env.IPINFO_API_KEY
  • Capabilities: Geolocation, ASN, organization, abuse contacts, privacy detection
  • Rate limits: Check API plan
  • Client: tools/​ipinfo-client.ts

System Tools (always available)

  • whois - Domain and IP WHOIS lookups
  • dig - DNS queries
  • nslookup - DNS resolution
  • curl - HTTP requests, API calls

MCP Tools (security profile required)

  • httpx - HTTP probing and technology detection
  • naabu - Port scanning
  • Note: Requires security MCP profile (~/​.claude/​MCPs/​swap-mcp security)

Future Tool Integration

Shodan (when API key added)

  • Search for exposed services
  • Historical scan data
  • Vulnerability information

Censys (when API key added)

  • Certificate searches
  • Host discovery
  • Internet-wide scanning data

SecurityTrails (when API key added)

  • Historical DNS records
  • WHOIS history
  • Subdomain discovery

VirusTotal (when API key added)

  • Domain/​IP reputation
  • Passive DNS
  • Malware associations

TypeScript Utilities

Located in tools/ directory:

ipinfo-client.ts

  • IPInfo API wrapper with error handling
  • Batch lookup support
  • Rate limiting
  • Response parsing

dns-utils.ts

  • DNS enumeration helpers
  • Record type queries
  • Zone transfer attempts
  • Subdomain brute forcing

whois-parser.ts

  • WHOIS data parsing
  • Structured output from raw WHOIS
  • Registration date extraction
  • Contact information parsing

cidr-utils.ts

  • CIDR notation parsing
  • IP range calculation
  • Range validation
  • IP address generation from CIDR

cert-transparency.ts

  • crt.sh API client
  • Certificate search
  • Subdomain extraction from certificates
  • Historical certificate data

report-generator.ts

  • Markdown report formatting
  • JSON output generation
  • Structured data presentation
  • Integration with OSINT reports

Output Formats

IP Reconnaissance Report

# IP Reconnaissance: 1.2.3.4

## Summary
- IP: 1.2.3.4
- Organization: Example Corp
- ASN: AS12345
- Location: San Francisco, CA, US
- ISP: Example Hosting

## DNS
- Reverse DNS: server.example.com
- Additional PTR: ...

## Network Information
- CIDR: 1.2.3.0/​24
- Netblock Owner: Example Corp
- Abuse Contact: [email protected]

## Services (Passive)
- Certificates: 3 certificates found
- Historical DNS: ...

## Services (Active - Authorized)
- Open Ports: 22, 80, 443
- Services: SSH (OpenSSH 8.2), HTTP (nginx 1.20.1), HTTPS
- Technologies: nginx, OpenSSH

## Recommendations
- Further investigation areas
- Related assets
- Security observations

Domain Reconnaissance Report

# Domain Reconnaissance: example.com

## Summary
- Domain: example.com
- Registrar: Example Registrar
- Registration: 2010-01-15
- Expiry: 2026-01-15

## DNS Records
### A Records
- 1.2.3.4
- 5.6.7.8

### MX Records
- 10 mail.example.com

## Subdomains
- www.example.com (1.2.3.4)
- api.example.com (1.2.3.5)
- admin.example.com (1.2.3.6)

## Email Security
- SPF: Configured
- DMARC: Configured
- DKIM: Configured

## Technologies
- Web Server: nginx
- Framework: React
- CDN: Cloudflare

## Recommendations
- Interesting subdomains: admin.example.com, api.example.com
- Attack surface: 15 web applications identified

Reports saved to:

  • Work scratch/​ (~/​.claude/​MEMORY/​WORK/​{current_work}/​scratch/) - For iterative artifacts during investigation
  • MEMORY/​RESEARCH/​ (~/​.claude/​MEMORY/​RESEARCH/​YYYY-MM/) - For pentest engagements and formal assessments

MCP Profile Requirements

For passive recon: No special MCP profile needed

For active recon: Requires security MCP profile

# Switch to security profile
~/​.claude/​MCPs/​swap-mcp security

# Restart Claude Code to apply
# Then run active reconnaissance

Security profile includes:

  • httpx (HTTP probing)
  • naabu (port scanning)
  • Other security tools

Ethical and Legal Considerations

CRITICAL RULES:

  1. Authorization First - Never perform active scanning without explicit authorization
  2. Scope Validation - Ensure targets are in-scope for testing
  3. Rate Limiting - Respectful scanning, no DoS or aggressive techniques
  4. Documentation - Log all recon activities with timestamps and authorization
  5. Responsible Disclosure - If vulnerabilities found, follow responsible disclosure
  6. No Destructive Testing - Reconnaissance only, no exploitation

Authorization Types:

  • Pentest engagement (written SOW/​contract)
  • Bug bounty program (in-scope targets only)
  • Owned assets (your own infrastructure)
  • Research lab/​CTF environments

Never scan:

  • Systems without permission
  • Out-of-scope targets
  • Critical infrastructure
  • Government systems (without specific authorization)

When in doubt: Ask for explicit confirmation and documented authorization.

Usage Examples

Example 1: Passive Domain Recon

User: "Do passive recon on example.com"

Assistant: Activating recon skill with passive-recon workflow.
     Target: example.com
     Mode: Passive only (no active scanning)

     [Performs WHOIS, DNS, cert transparency, IPInfo]
     [Generates report in scratchpad]

     Report: ~/​.claude/​MEMORY/​WORK/​{current_work}/​scratch/​recon-example-com/

Example 2: IP Investigation with Active Scan

User: "Investigate IP 1.2.3.4 - I own this server"

Assistant: Activating recon skill with ip-recon workflow.
     Target: 1.2.3.4

     Authorization check: You confirmed this is an owned asset.
     Proceeding with passive + active reconnaissance.

     [Performs IPInfo, reverse DNS, WHOIS, port scan, service detection]
     [Generates comprehensive report]

     Report: Open ports found (22, 80, 443)
             Services: SSH, HTTP, HTTPS
             Technologies: nginx 1.20.1, OpenSSH 8.2

Example 3: Integration with OSINT

User: "Do OSINT on Acme Corp and map their infrastructure"

Assistant: Activating OSINT skill...
     Found domains: acme.com, acmecorp.com, acme.io

     Now calling recon for infrastructure mapping...

     [Recon skill maps each domain]
     [Discovers subdomains, IPs, netblocks]
     [Creates comprehensive infrastructure map]

     Report: Complete OSINT + Infrastructure report
             15 domains, 47 subdomains, 3 netblocks identified

Workflow Selection Logic

Automatic workflow selection based on input:

  • Input matches IP pattern (x.x.x.x) → IpRecon.md
  • Input matches domain pattern → DomainRecon.md
  • Input matches CIDR pattern (x.x.x.x/​y) → NetblockRecon.md
  • Input matches ASN pattern (AS####) → AsnRecon.md
  • User specifies "passive only" → PassiveRecon.md

User can override:

"Use passive-recon workflow on 1.2.3.4"
"Run domain-recon on example.com with active scanning"

Success Criteria

Passive Recon Success:

  • WHOIS data retrieved
  • DNS records enumerated
  • Certificate transparency searched
  • IPInfo data gathered
  • Structured report generated

Active Recon Success:

  • Authorization confirmed and documented
  • Passive recon completed first
  • Port scan results (open/​closed/​filtered)
  • Service detection performed
  • Banner information gathered
  • Technologies identified
  • No errors or failures
  • Respectful scan timing (no DoS)

Related Documentation

Security Skills:

  • ~/​.claude/​skills/​OSINT/ - Entity and people reconnaissance
  • ~/​.claude/​skills/​Webassessment/ - Web application testing

Tool Documentation:

Best Practices:


Remember: Start passive, confirm authorization before going active, document everything, and be respectful of target systems.

More Security skills

supabase logo
Security

supabase

Handles the full Supabase workflow from schema changes to deployment, with built-in security guardrails that catch common traps like RLS...

2.7K 308.9K
View

Comprehensive guides and best practices for Neon Serverless Postgres, covering setup, connection methods, authentication, and platform APIs.

98 216.2K
View

Guide for setting up and using Firebase Authentication. Use this skill when the user's app requires user sign-in, user management, or secure data access using auth rules.

462 163.8K
View

A skill to evaluate how secure Firestore security rules are. Use this when Firestore security rules are updated to ensure that the generated rules are extremely secure and robust.

462 127.7K
View

Official skill for integrating Firebase AI Logic (Gemini API) into web applications. Covers setup, multimodal inference, structured output, and security.

462 125.1K
View

Complete Better Auth server and client setup with database adapters, session management, plugins, and security configuration.

222 118.2K
View

Deploy and manage projects on Vercel using token-based authentication. Use when working with Vercel CLI using access tokens rather than interactive login — e.g. "deploy to vercel", "set up vercel", "add environment variables to vercel".

31.9K 116.1K
View
cloudflare logo
Security

cloudflare

Complete Cloudflare platform integration with decision trees for compute, storage, AI, networking, security, and infrastructure-as-code.

3K 110.7K
View

Run Azure compliance and security audits with azqr plus Key Vault expiration checks. Covers best-practice assessment, resource review, policy/compliance validation, and security posture checks. WHEN: compliance scan, security audit, BEFORE running azqr (compliance cli tool), Azure best practices, Key Vault expiration check, expired certificates, expiring secrets, orphaned resources, compliance assessment.

253 103K
View
gws-gmail logo
Security

gws-gmail

Send, read, and manage Gmail messages, drafts, labels, and account settings.

31.2K 78.9K
View

Comprehensive website auditing across 230+ rules in 21 categories including SEO, performance, security, and accessibility.

94 72.3K
View
gws-shared logo
Security

gws-shared

Shared authentication, CLI syntax, and output formatting patterns for gws Google Workspace commands.

31.2K 63.4K
View

Security AI tools

StarByFace logo
Security

StarByFace

Discover your celebrity doppelgänger with StarByFace!

Free
View
GeoSpy logo
Security

GeoSpy

GeoSpy: Pricing, Features, FAQs, and Alternatives for AI Teams

Free
View

Detect AI-generated voices to protect against audio fraud.

Paid
View

Ensure Your Content's Originality with AI Plagiarism Checker

Freemium
View
Img Upscaler logo
Security

Img Upscaler

Upscale images by 400% without quality loss

Freemium
View
AICheatCheck logo
Security

AICheatCheck

Accurately Detect AI-Generated Content with TheChecker.AI

Free
View
D
Security

Detect GPT

Chrome extension that detects and flags AI-generated content

Free
View