Subdomain Takeover using readthedocs

Hello World!

Not a fancy blog post, but I just discovered that subdomain takeover is possible for "readthedocs."

What is a subdomain takeover?
It is best explained here.

What is "readthedocs"?
Read the Docs is an open-sourced free software documentation hosting platform. It generates documentation written with the Sphinx documentation generator.

How do I check for subdomain takeover over?

Any subdomain pointing to "readthedocs" but not claimed would throw an error like in the screenshot below.

How to takeover?
1. Signup at and click on Admin settings
2. Add the repository or fork the repository if you wish to make any changes.
3. Add your repository at "Repository URL:"

4. Click on "Domains" in admin settings and add the domain.


P.S I wrote this blog because I didn't find it mentioned at

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