securityskills Attack Surface Recon
Build a complete external attack-surface picture from public sources.
1. Root Domain Discovery
- Start from known brands/domains; expand via certificate transparency (crt.sh), ASN lookups, WHOIS reverse lookups, acquisition history
- Identify cloud ranges: enumerate owned netblocks (bgp.he.net, ipinfo)
2. Subdomain Enumeration
- Passive sources: CT logs, DNS datasets (SecurityTrails-style), web archives
- Active: DNS bruteforce, permutation generation (alterations of known hosts:
-dev,-staging,-old) - Resolve; probe HTTP(S) for live services; fingerprint technologies (httpx/wappalyzer)
3. Exposed Services
- Port scan in-scope IPs (top ports minimum, full range on high-value hosts)
- Flag: exposed admin panels, databases (3306/5432/27017), RDP/SMB, Redis/Memcached, Kubernetes API, VPN portals, file shares
- Takeover checks: dangling CNAMEs pointing at deprecated cloud services
4. Credential and Code Leaks
- Breach data for corporate domains (report presence; never view more than proof)
- Public code search (GitHub/gists) for org domains, tokens, internal hostnames in commits
- Exposed storage: open S3 buckets/azure blobs matching org naming patterns
5. People and Brand
- Employee enumeration via LinkedIn for phishing-simulation scoping (policy permitting)
- Lookalike domains registered recently (typosquats), abuse of brand in app stores
Rules
- Passive sources preferred; active scanning only within authorization
- Found leaked credentials: report immediately, do not log in with them
Output
Ranked asset inventory: exposed services by risk, credential leak notifications, takeover-prone records, and monitoring recommendations.