Kali Linux

Factual-Rules-Generator : An Open Source Project Which Aims To Generate YARA Rules

Factual-rules-generator is an open source project which aims to generate YARA rules about installed software from a running operating system.

The goal of the software is to be able to use a set of rules against collected or acquired digital forensic evidences and find installed software in a timely fashion.

The software can be used to baseline known software from Windows system and create a set of rules for finding similar installation on other systems.

Dependencies

  • pefile
  • psutil
  • ndjson
  • python-tlsh
  • PyInstaller (to change client.py to client.exe)
  • ssdeep
    • On Ubuntu:
      • sudo apt-get install build-essential libffi-dev python3 python3-dev python3-pip libfuzzy-dev
      • pip install ssdeep

Tools requirement

Some tools are required on the host operating system some are Unix standard tools and some additional ones:

  • xxd
  • curl

For the Windows virtual machine, the following software is required to be installed:

  • SDelete
  • AsA (AttackSurfaceAnalyzer)

Install

  • Install all Python dependencies defined requirements.txt
  • Create a shared folder to communicate with VM
  • Install a Windows VM
    • Install chocolatey on Windows VM
    • Complete bin/OnWindows/Varclient.py
    • Change bin/OnWindows/client.py in an executable file with PyInstaller and put in startup folder
  • Update etc/allVariables.py to match your desired configuraiton

In test/ some examples of software to install is given, the following specific format is required:

  • First, select the name of the packages to install using chocolatey before :, or the name of the file in case of msi or exe file.
  • Second, after : there’s the name of the exe to extract and run it (without extension).
  • The second part after , follow the same system with the word installer first and after : the type of installer :
    • choco
    • msiexec
    • exe
  • Finally, the third part, uninstaller follow by : and the uninstaller like choco, msiexec or exe

Run and generate the rules

  • bin/Generator.py is the only script to run, don’t forget to update etc/allVariables.py (critical step).

Public YARA rules repository

  • factual-rules – Sample rules generated from some very common software.

Overview of factual rules generator

R K

Recent Posts

Why Deploying AI Is Just the Beginning: The Case for Ongoing AI Operations Monitoring

Most enterprise AI programs treat deployment as the destination. The business case is built around…

14 hours ago

Bash Scripting Best Practices Every Beginner Should Know

Introduction Bash scripting is a powerful way to automate Linux tasks, but writing a script…

5 days ago

How To Create A Self-Signed SSL Certificate Using Bash And OpenSSL

Introduction A self-signed SSL certificate is a certificate that is created and signed by the…

6 days ago

How To Debug Bash Scripts Using bash -x And set Commands

Introduction Debugging is an important part of Bash scripting. When a script does not work…

6 days ago

How To Use Cron Jobs With Bash Scripts For Automation

Introduction Cron jobs are used in Linux to run commands or Bash scripts automatically at…

6 days ago

How To Use Pipes In Bash Scripts For Command Chaining

Introduction Pipes are an important feature in Linux and Bash scripting. A pipe allows you…

6 days ago