> For the complete documentation index, see [llms.txt](https://sidxparab.gitbook.io/subdomain-enumeration-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sidxparab.gitbook.io/subdomain-enumeration-guide/types/vertical-enumeration.md).

# Vertical Enumeration

Vertical Enumeration or Vertical domain correlation is a process of finding out hosts located on the same root domain. This type of enumeration contains various techniques and can be automated too.

Here, we find different levels of subdomains of a particular root/main domain.

![](/files/-MbuTvemzy77asWu0SnO)

Vertical Enumeration can be performed with the help of below mentioned techniques: 

1. **Passive Techniques**
   * Passive Sources 
   * Certificates Logs
2. **Active Techniques**
   * DNS bruteforcing
   * Permutations/Alterations
   * JS/Source Code Scraping
   * VHOST discovery
   * Google Analytics
   * Recursive Enumeration
   * TLS, CSP, CNAME probing
   * Regex Permutations
3. **Web probing**
   * Default Ports
   * Common Ports

Each and every technique is explained in detail, so read out the whole guide. :blush: 


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