OSINT Recon — Open Source Intelligence Gathering

Systematically gather, analyze, and correlate publicly available information from open sources.

Ethics Check

Before proceeding, confirm:

1. The investigation has a legitimate purpose (threat intel, authorized assessment, CTF, defensive research)
2. You are only gathering publicly available information
3. Results will not be used for harassment, stalking, or doxing

Refuse requests that target individuals for harassment or aggregate private information beyond what the objective requires.

Collection Techniques

Domain and Infrastructure OSINT

Run these to map a target's infrastructure:

whois <domain>                  # Registration data
dig any <domain>                # DNS records

Query certificate transparency for subdomains:

curl -s "https://crt.sh/?q=%25.<domain>&output=json" | jq -r '.[].name_value' | sort -u

Additional sources: SecurityTrails, DNSDumpster, ipinfo.io, bgp.he.net, Wayback Machine, Shodan, Censys.

Organization OSINT

• Company registrations, filings, SEC records (public companies)
• LinkedIn company page — employee count, roles, tech stack hints
• Job postings — reveal internal tools, tech stack, pain points
• Press releases and news articles
• GitHub/GitLab organization pages and public repositories
• Patent filings

Email and Username OSINT

• Email format patterns (e.g., [email protected])
• HaveIBeenPwned — check for breach exposure (check only, never distribute breach data)
• PGP key servers for email discovery
• Gravatar lookups for email-to-identity correlation

Document and File OSINT

• Extract metadata from public documents: exiftool <file> reveals author, software, GPS, timestamps
• Google dorking: site:<domain> filetype:pdf, site:<domain> filetype:xlsx
• Pastebin and code paste site monitoring
• Public cloud storage enumeration (S3 buckets, GCS buckets with predictable names)

Threat Intelligence

• CVE databases for the target's technology stack
• Exploit databases (exploit-db, searchsploit)
• Threat feeds and IOC databases (VirusTotal, MalwareBazaar, OTX)
• Abuse contact databases

Analysis

• Cross-reference findings across multiple sources
• Validate information with at least two independent sources
• Build a timeline of events when investigating incidents
• Map relationships between entities (people, domains, IPs, organizations)
• Rate confidence: High (multiple corroborating sources), Medium (single reliable source), Low (unverified)

Output Format

# OSINT Report
## Objective: [what we're investigating and why]
## Target: [entity/domain/person]
## Date: [date]

### Collection Summary
| Source | Findings | Confidence |
|--------|----------|------------|

### Key Findings

#### Finding 1: [Title]
- **Source:** [where this was found]
- **Details:** [what was discovered]
- **Confidence:** High / Medium / Low
- **Relevance:** [why this matters to the objective]

### Correlations
[How different findings connect to each other]

### Intelligence Gaps
[What we couldn't find or verify]

### Recommendations
[Next steps and actionable intelligence]

Boundaries

• Only use publicly available sources
• Never attempt to access private or authenticated systems
• Do not aggregate PII beyond what is necessary for the stated objective
• Attribute all findings to their source
• Rate confidence levels honestly — do not overstate certainty
• If a finding could cause harm if misused, note the sensitivity
• Refuse requests for doxing, stalking, or unauthorized surveillance

References

• OSINT Framework (osintframework.com)
• SANS OSINT resource list
• Bellingcat Online Investigation Toolkit