Favicon Hash Bug Bounty Recon

Passive infrastructure mapping and advanced techniques for 2026.


Why favicon hashing is a top recon technique

  • • Zero active scanning — no traffic reaches the target during discovery
  • • Finds hosts not in DNS records (forgotten servers, dev instances)
  • • Bypasses WAFs by finding origin IP behind CDN via favicon match
  • • Works across the entire internet simultaneously via search platforms
  • • Reveals technology stack immediately — no scanning needed

The favicon recon workflow

1

Hash target domain → paste https://target.com into FaviconHasher

2

Multi-platform search → click all 8 platform links for max coverage

3

Identify related infrastructure → hosts sharing same favicon are likely in-scope

4

Cross-reference with scope → check which IPs/domains are in the bug bounty program

5

Fingerprint technologies → use our database to identify what's running

6

Target known vulns → Spring Boot? Check /actuator. Jenkins? Check /script.

Multi-platform pivoting strategy

Different platforms have different coverage. Always query all of them — FOFA often returns 10× more than Shodan.

Automation with the API

import requests
for url in ["https://target.com", "https://app.target.com"]:
    r = requests.get("https://faviconhasher.codejavu.tech/api/v2", params={"url": url})
    d = r.json()
    print(d["hashes"]["mmh3"], d["technology"], d["links"]["shodan"])