CRTFinder

CRTFinder is a simple tool to retrieve a list of subdomains for a given domain using data from crt.sh, a website that provides public SSL certificate information. The tool automatically removes duplicate subdomains and ensures that only valid subdomains are displayed.

Features

• Fetch subdomains from a specified domain.
• Supports single domain input or a list of domains from a file.
• Automatically removes duplicate subdomains.
• Cleans subdomains by removing www. prefixes and wildcard *.
• Filters out invalid domain inputs.

Installation

1. Clone the repository:

   git clone https://github.com/mnovel/CRTFinder.git
   cd CRTFinder

2. Install dependencies:

   CRTFinder uses the requests module, make sure it is installed. If not, run the following command:

   pip install requests

3. Run the script:

   CRTFinder can be executed from the command line. Use Python 3.x to run it.

   python CRTFinder.py -d example.com

Usage

There are two ways to use CRTFinder:

1. Fetch subdomains for a single domain:

   Use the -d or --domain option to specify the domain you want to retrieve subdomains for.

   python CRTFinder.py -d example.com

2. Fetch subdomains from a file with multiple domains:

   You can provide a file containing a list of domains using the -f or --file option.

   Each line in the file should contain one domain:

   example.com
   example.org
   test.com
   

   Then, run:

   python CRTFinder.py -f domainlist.txt

Output

Once executed, the tool will display the unique subdomains found. Here's an example of the output:

Unique Subdomains:
api.example.com
mail.example.com
www.example.com

Options

• -d or --domain: Specify a domain to retrieve subdomains for.
• -f or --file: Specify a file containing a list of domains to retrieve subdomains from.
• -h or --help: Display a help message and list available options.

Example Usage

Example 1: Fetch subdomains for a single domain

python CRTFinder.py -d example.com

Example 2: Fetch subdomains from a file with multiple domains

python CRTFinder.py -f domainlist.txt

License

This project is licensed under the MIT License.