
Chepy¶
Solving a CTF with Chepy
Chepy is a python library with a handy cli that is aimed to mirror some of the capabilities of CyberChef. A reasonable amount of effort was put behind Chepy to make it compatible to the various functionalities that CyberChef offers, all in a pure Pythonic manner. There are some key advantages and disadvantages that Chepy has over Cyberchef. The Cyberchef concept of stacking different modules is kept alive in Chepy.
There is still a long way to go for Chepy as it does not offer every single ability of Cyberchef.
Example¶
For all usage and examples, see the docs.
Chepy has a stacking mechanism similar to Cyberchef. For example, this in Cyberchef:

This is equivalent to
from chepy import Chepy
file_path = "/tmp/demo/encoding"
print(
Chepy(file_path)
.load_file()
.reverse()
.rot_13()
.base64_decode()
.base32_decode()
.hexdump_to_str()
.o
)
Installation¶
Chepy can be installed in a few ways.
Pypi¶
pip3 install chepy
Git¶
git clone https://github.com/securisec/chepy.git
cd chepy
pip3 install -e .
# I use -e here so that if I update later with git pull, I dont have it install it again (unless dependencies have changed)
Pipenv¶
git clone https://github.com/securisec/chepy.git
cd chepy
pipenv install
Docker¶
docker run --rm -ti -v $PWD:/data securisec/chepy "some string" [somefile, "another string"]
Chepy vs Cyberchef¶
Advantages¶
- Chepy is pure python with a supporting and accessible python api
- Chepy has a CLI
- Chepy CLI has full autocompletion.
- Extendable via plugins
- Infinitely scalable as it can leverage the full Python library.
- Chepy can interface with the full Cyberchef web app to a certain degree. It is easy to move from Chepy to Cyberchef if need be.
- The Chepy python library is significantly faster than the Cyberchef Node library.
- Works with HTTP/S requests without CORS issues.
Disadvantages¶
- Chepy is not a web app (at least for now).
- Chepy does not offer every single thing that Cyberchef does
- Chepy does not have the
magic
method (at the moment)
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