Flask-Unsign - Command line tool to fetch, decode, brute-force an

项目说明

Flask Unsign

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Command line tool to fetch, decode, brute-force and craft session cookies of a Flask application by guessing secret keys.
For the standalone wordlist component, please visit the flask-unsign-wordlist repository.

Requirements

* Python 3.6+

Installation

To install the application, simply use pip:

If you only want to install the core code, omit the [wordlist] suffix:

To install the tool for de purposes, run the following command (after downloading a copy):

Usage

To get an o of all possible options, simply call flask-unsign without
any arguments like so:

Obtaining & Decoding Session Cookies

Due to the fact that Flask cookies are signed and not encrypted, it's
possible to locally decode the session data. For this, you can use the --decode
argument.

Session cookies can be obtained by inspecting your HTTP requests using a proxy
like Burp Proxy, using your browser's network inspector or using a browser
extension to view/change your cookies. By default, Flask uses the session name
"session".

You can also use Flask-Unsign's automatic session grabbing functionality by
passing the --server argument, instead of the --cookie argument. *Do note
however, that not all web pages might return a session, so be sure to pass an
url which does.*

Unsigning (Brute Forcing Secret Keys)

After obtaining a sample session cookie, you'll be able to attempt to brute-force
the server's secret key. If you're lucky, this might be set to something easy to
guess, or if it's been found online, it might be in one of your wordlists. For
this, you can use the --unsign argument.

Signing (Session Manipulation)

Once you' the server's secret key, you'll be able to craft your own
custom session data. For this, you can use the --sign argument.

Troubleshooting

* Installing the program results in an error
* You might be using the wrong pip binary, try using
the following command: python3.6 -m pip install flask-unsign
* I found a secret key, but my crafted sessions don't work!
* It might be possible that your target server uses an older of
itsdangerous. Due to
an issue with timed
sessions, the timestamp generation algorithm was changed.
To generate an older signature, try using the --legacy option.
* My wordlist doesn't work
* Wordlists expect to be newline delimited
python strings
(meaning you need to encapsulate them in quotes), this is so that
binary strings can easily be stored in a newline format. If you don't want
this, you can disable this feature by passing the --no-literal-eval
argument.

How it works

If you're wondering how exactly this works, refer to my
blog post
which explains this in great detail, including a guide on how to protect your own server from this attack.

License

MIT License

Copyright (c) 2021 Luke Paris (Paradoxis)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The abo notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

项目信息

开发语言：Python

Star 数：663

技术要点

该项目属于CTF思路方向的开源资源，代码结构清晰，适合安全研究人员学习参考。项目围绕Command line tool to fetch, decode, brute-force and craft session cookies of a Flask application by guessing secret keys.展开，提供了可运行的实现，对理解相关安全机制、工具原理与攻防技术具有较高的研究价值。

从技术实现角度看，此类项目的核心在于对底层原理的深入理解与工程化落地。开发者在研究过程中可以结合官方文档与社区讨论，梳理项目的初始化流程、核心模块职责与数据流转，逐步掌握其中的技术细节与设计思路。

使用与学习建议

1. 下载源码压缩包，解压到本地环境。

2. 根据项目类型准备对应的运行环境与依赖。

3. 按照 README 中的步骤完成配置与部署。

4. 在隔离的测试环境中运行验证，避免影响生产系统。

免责声明

本资源来源于开源社区，仅供安全研究、技术学习与合法授权范围内的攻防演练使用，请勿用于任何非法或侵害他人权益的用途。使用本项目产生的一切后果由使用者自行承担。