Updated Jul 14, 2026

Recon

Group hosts by favicon hash and pivot with Shodan

Hash favicons across a URL list and match them against a fingerprint dictionary.

Agent

overview

What favfreak does

favfreak reads a URLs file from stdin, fetches each favicon.ico, computes MurmurHash3, and groups hosts by hash against a bundled fingerprint dictionary.

Enable --shodan to emit http.favicon.hash dorks. Paste those into Shodan to find other hosts serving the same icon and widen scope past the original list.

Trickest runs it as a managed recon node after httpx or similar probing. Prefer favup when you need the origin IP behind one CDN-fronted host instead of clustering a list.

source github.com/devanshbatham/FavFreak

use cases

Where favfreak fits

Fingerprint tech by favicon

Hash the favicon of every URL in a list to group hosts by the software and framework behind them, surfacing the stack without active fingerprinting.

Generate Shodan dorks for pivoting

Turn computed favicon hashes into http.favicon.hash dorks with --shodan, then search Shodan for other hosts serving the same icon to widen the asset map.

Cluster an organization's assets

Group hosts that share a favicon to map an organization's properties, which helps scope an engagement or spot shadow assets that reuse a known icon.

Triage a probed surface

Run it after httpx to attach a tech label to each live host, so later stages focus on the stacks worth testing instead of the whole list.

reference

favfreak inputs and flags

2 inputs
NameTypeFlagDescription
urlsFILE·URLs to scan; the favicon.ico of each is fetched and hashed.
shodanBOOLEAN--shodanGenerate Shodan dorks (http.favicon.hash) from the computed hashes.

Showing key inputs. favfreak exposes 2 inputs in total.

example

Run favfreak

favfreak · command
# hash every favicon in a URL list and emit Shodan dorkscat urls.txt | favfreak --shodan
sample output
[ 116323821 ]    http://example.com    http://www.example.com[ -1968997567 ]    http://app.example.com[ 81586312 ]    http://staging.example.com[ Shodan Dorks ]http.favicon.hash:116323821http.favicon.hash:81586312

guidance

Choosing favfreak

Fingerprint a live URL list by favicon hash and optionally emit Shodan dorks. Run after discovery and probing. Use favup to unmask a single CDN origin.

favup

Resolves the real IP behind a favicon via Shodan. favfreak fingerprints tech and builds dorks across a list.

httpx

Probes hosts and detects technologies per request. favfreak adds favicon-hash grouping and Shodan pivoting.

wappalyzer

Detects web technologies from page content. favfreak uses the favicon hash as the fingerprint signal instead.

faq

favfreak questions

A favicon hash is a stable fingerprint of the app, CDN, or admin panel serving it. Identical hashes across hosts usually mean the same technology or organization, so favfreak clusters assets without active stack fingerprinting.

Run favfreak yourself

A URL list feeds favfreak, which hashes each favicon, matches the fingerprint dictionary, and writes the grouped tech results as output.

Facts on this page come from the live Trickest tool library.