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recon

Perform structured reconnaissance and attack surface enumeration for authorized penetration tests, CTF challenges, and bug bounty programs. Use when the user mentions 'recon,' 'reconnaissance,' 'enumerate,' 'attack surface,' 'subdomain enumeration,' 'port scan,' 'fingerprint,' 'asset discovery,' or needs to map a target's external footprint.

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88%

Does it follow best practices?

Impact

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SecuritybySnyk

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SKILL.md
Quality
Evals
Security

Recon — Penetration Testing Reconnaissance

Perform structured reconnaissance against an authorized target, organizing findings into an actionable attack surface map.

Authorization Check

Before running any commands, confirm:

  1. The user has written authorization for the target (pentest engagement, bug bounty program, CTF/lab environment)
  2. The target is within the defined scope

If authorization is unclear, ask before proceeding. Never assume authorization.

Methodology

Phase 1: Passive Recon

Gather information without touching the target directly.

DNS enumeration:

  • Run dig any $ARGUMENTS for A, AAAA, MX, TXT, NS, CNAME records
  • Attempt zone transfer: dig axfr @ns-server $ARGUMENTS
  • Enumerate subdomains via certificate transparency:
    curl -s "https://crt.sh/?q=%25.$ARGUMENTS&output=json" | jq -r '.[].name_value' | sort -u

WHOIS and registration: Run whois $ARGUMENTS for registrant, nameserver, and creation date info.

Search engine dorking: Use targeted queries — site:, inurl:, filetype:, intitle: — to find exposed pages, documents, and admin panels.

Technology fingerprinting: Identify frameworks, CMS, server software, and JavaScript libraries from public-facing pages.

Public code repositories: Search GitHub/GitLab for the target's org name, domain, API keys, or internal paths.

Historical data: Check the Wayback Machine for old endpoints, removed pages, and configuration files.

Phase 2: Active Recon (explicit authorization only)

Port scanning:

nmap -sC -sV -oN scan-results.txt $ARGUMENTS

Start with top 1000 ports. Expand to full range (-p-) if needed. Use -Pn if the host appears down but is in scope.

Service enumeration: Based on open ports, probe for version info and default configurations.

Web content discovery:

  • Directory bruting with gobuster, feroxbuster, or dirsearch
  • Virtual host enumeration
  • API endpoint discovery (check /api/, /v1/, /graphql, /swagger.json)

SSL/TLS analysis: Run testssl.sh or sslyze to check for weak ciphers, expired certificates, and misconfigurations.

Phase 3: Analysis

Correlate all findings. Identify the most promising attack vectors and prioritize by:

  1. Severity of potential impact
  2. Likelihood of exploitation
  3. Exposure level (internet-facing vs. internal)

Output Format

Produce a structured recon report:

# Recon Report
## Target: [target]
## Scope: [confirmed scope]
## Date: [date]

### Passive Findings
| Finding | Details | Relevance |
|---------|---------|-----------|

### Subdomains Discovered
- [list]

### Technologies Detected
- [list with versions where identified]

### Active Findings
| Port | Service | Version | Notes |
|------|---------|---------|-------|

### Attack Surface Summary
[Prioritized list of interesting findings with risk assessment]

### Recommended Next Steps
[Ordered list of what to investigate further]

Boundaries

  • Stay within the defined scope — never scan adjacent or out-of-scope systems
  • Rate-limit aggressive scans to avoid disruption
  • Log all commands run for the engagement record
  • If you discover evidence of active compromise by a third party, alert the user immediately
  • Refuse requests targeting systems without explicit authorization
  • Refuse requests for mass scanning of unrelated targets

References

  • PTES (Penetration Testing Execution Standard)
  • OWASP Testing Guide
  • Bug Bounty Methodology (jhaddix/tbhm)
Repository
briiirussell/cybersecurity-skills
Last updated
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