To run the script, Python 3+ is required. Also, make sure to install the following Python libraries (most are shipped by default):
argparsebase64randomgzipurllibmagic
You can install the required libraries using pip:
python3 -m pip install --user -r requirements.txtYou can run the encoder script with the following command:
python3 encoder.py {random,base64,uri or unicode} [--gzip] input.html output.html If you use the random flag, the script will execute all encoding methods a random number of times between one and ten. The encoding_steps should not go above 10, as large files can be generated based on input size. Each method produces a different filesize increase factor, as shown in the table below:
| Encoding Type | Filesize Increase Factor |
|---|---|
| Unicode | ~6 |
| URI | ~3 |
| Base64 | ~1.34 |
To compress the output file and insert it into a webpage that will self-extract with pako (imported at runtime from Cloudflare CDN), use the --gzip flag.
The decoder script can be run using the following command:
python3 decoder.py [--cyberchef] input.html output.htmlTo output the corresponding CyberChef recipe to a JSON file for easy import, use the --cyberchef flag.
Included in this project are several webpages for testing purposes:
example.html: a simple "Hello World" webpage to test basic functionality.exampleCoffeeHouse.html: slightly more complex, including an image (mime type base64) and some URLs that can be extracted in CyberChef.calc.html: a simple JS calculator, with the code having been passed through an online obfuscator, although the original code is still contained within.
- Add a method to search for and decode
decodeURIComponent()ordecodeURI() - Think of how to get encoded data by reference.
- Think of how to deal with multiple encoding methods at the end, for example, a file that has multiple atobs or unicodes at the end.
- Consider having a step mode so the decoder will do one step at a time and show what happens at each step.