Second Order - Subdomain Takeover Scanner

Overview

Scans web applications for second-order subdomain takeover by crawling the app, and collecting URLs (and other data) that match certain rules, or respond in a certain way.

Installation

From binary

Download a prebuilt binary from the releases page and unzip it.

From source

Go version 1.17 is recommended.

go install -v github.com/mhmdiaa/second-order@latest

Docker

docker pull mhmdiaa/second-order

Configuration File

Example configuration files are in config

LogQueries: A map of tag-attribute queries that will be searched for in crawled pages. For example, "a": "href" means log every href attribute of every a tag.
LogNon200Queries: A map of tag-attribute queries that will be searched for in crawled pages, and logged only if they contain a valid URL that doesn’t return a 200 status code.
LogInline: A list of tags whose inline content (between the opening and closing tags) will be logged, like title and script

Usage Ideas

This is a list of tips and ideas (not necessarily related to second-order subdomain takeover) on what to use Second Order for.

Check for second-order subdomain takeover: takeover.json. (Duh!)
Collect inline and imported JS code: javascript.json.
Find where a target hosts static files cdn.json. (S3 buckets, anyone?)
Collect <input> names to build a tailored parameter bruteforcing wordlist: parameters.json.
Feel free to contribute more ideas!