Reverse Engineering

PE Tree – Python Module For Viewing Portable Executable (PE) Files

PE Tree - Python Module For Viewing Portable Executable (PE) Files In A Tree-View

 

Python module for viewing Portable Executable (PE) files in a tree-view using pefile and PyQt5. Can also be used with IDA Pro to dump in-memory PE files and reconstruct imports.

Features

  • Standalone application and IDAPython plugin
  • Supports Windows/Linux/Mac
  • Rainbow PE ratio map:
    • High-level overview of PE structures, size and file location
    • Allows for fast visual comparison of PE samples
  • Displays the following PE headers in a tree view:
    • MZ header
    • DOS stub
    • Rich headers
    • NT/File/Optional headers
    • Data directories
    • Sections
    • Imports
    • Exports
    • Debug information
    • Load config
    • TLS
    • Resources
    • Version information
    • Certificates
    • Overlay
  • Extract and save data from:
    • DOS stub
    • Sections
    • Resources
    • Certificates
    • Overlay
  • Send data to CyberChef
  • VirusTotal search of:
    • File hashes
    • PDB path
    • Timestamps
    • Section hash/name
    • Import hash/name
    • Export name
    • Resource hash
    • Certificate serial
  • Standalone application;
    • Double-click VA/RVA to disassemble with capstone
    • Hex-dump data
  • IDAPython plugin:
    • Easy navigation of PE file structures
    • Double-click VA/RVA to view in IDA-view/hex-view
    • Search IDB for in-memory PE files;
      • Reconstruct imports (IAT + IDT)
      • Dump reconstructed PE files
      • Automatically comment PE file structures in IDB
      • Automatically label IAT offsets in IDB

Application

Requirements

  • Python 3+

Installation

Using pip (recommended)
Install directly from GitHub using a fresh virtual environment and pip:

Windows

> virtualenv env
> envScriptsactivate
> pip install --upgrade pip
> pip install git+https://github.com/blackberry/pe_tree.git

Mac/Linux

$ python3 -m venv env
$ source ./env/bin/activate
$ pip install --upgrade pip
$ pip install git+https://github.com/blackberry/pe_tree.git

For developers
Git clone the repository and setup for development:

Windows

> git clone https://github.com/blackberry/pe_tree.git
> cd pe_tree
> virtualenv env
> envScriptsactivate
> pip install -e .

Mac/Linux

$ git clone https://github.com/blackberry/pe_tree.git
$ cd pe_tree
$ python3 -m venv env
$ source ./env/bin/activate
$ pip install -e .

Usage
Run PE Tree and use the GUI to select a file to view:
$ pe-tree
Run PE Tree and view the specified file/folder:
$ pe-tree <path>

Dark-mode
Dark-mode can be enabled by installing QDarkStyle:

$ pip install qdarkstyle

IDAPython

Requirements

  • IDA Pro 7.0+ with Python 2.7
  • IDA Pro 7.4+ with Python 2.7 or 3.x

Installation
To install and run as an IDAPython plugin you can either use setuptools or install manually.

Using setuptools

  1. Download pe_tree and install for the global Python interpreter used by IDA:
    $ git clone https://github.com/blackberry/pe_tree.git
    $ cd pe_tree
    $ python setup.py develop --ida
  2. Copy pe_tree_ida.py to your IDA plugins folder

Install manually

  1. Download pe_tree and install requirements for the global Python interpreter used by IDA:
    $ git clone https://github.com/blackberry/pe_tree.git
    $ cd pe_tree
    $ pip install -r requirements.txt
  2. Copy pe_tree_ida.py and the contents of ./pe_tree/ to your IDA plugins folder

For developers
To simply run as a script under IDA first install the pe_tree package requirements for the global Python installation:

$ pip install -r requirements.txt

Then run pe_tree_ida.py under IDA:
File -> Script file... -> pe_tree_ida.py -> Open

IDA plugins folder

OS Plugins folder
Windows %ProgramFiles%IDA Pro 7.Xplugins
Linux /opt/ida-7.X/plugins
Mac ~/.idapro/plugins

Usage

  1. Run IDA and disassemble a PE file (select Manual Load and Load Resources for best results!)
  2. Click Edit -> Plugins -> PE Tree

Examples

Dumping in-memory PE files
Below are the basic steps to dump a packed PE file (for example MPRESS or UPX) and rebuild imports (assuming the image base/entry-point is fairly standard):

  1. Launch IDA Pro and disassemble an MPRESS or UPX packed PE file (select Manual Load and Load Resources)
  2. Select debugger (Windows or Bochs) and run until OEP (usually 0x00401000)
  3. At this point you could take a memory snapshot (saving all segments) and save the IDB for later
  4. Ensure IDA has found all code Options -> General -> Analysis -> Reanalyze program
  5. Open PE Tree, right-click and choose Add PE -> Search IDB
  6. Right click on HEADER-0x00400000 (or appropriate module) and select Dump...
  7. Specify the AddressOfEntryPoint (typically 0x1000)
  8. Ensure Rebuild imports is selected
  9. Dump!

A new executable will be created using the unpacked section data obtained from memory/IDB, and a new section named .idata containing the rebuilt IAT, hint name table and IDT will be appended to the PE file. If the entry-point memory segment has been marked writable during execution (via VirtualProtect for example) then the EP section characteristics will also be marked writable. Finally, the BASERELOC, BOUND_IMPORT and SECURITY data directories are marked null, and the OPTIONAL_HEADER checksum is recalculated (if enabled via config)
Using the above approach it is possible to dump many in-memory PE files that have either been unpacked, remotely injected, reflectively loaded or hollowed etc.

Configuration

Overview
The configuration is stored in an INI file and defaults to the following values:

[config]
debug = False
fonts = Consolas,Monospace,Courier
virustotal_url = https://www.virustotal.com/gui/search
cyberchef_url = https://gchq.github.io/CyberChef
[dump]
enable = True
recalculate_pe_checksum = False

Options

Section Option Type Description
config debug boolean Print pefile.dump() to output
config fonts string Comma-separated list of font names for UI
config virustotal_url string VirusTotal search URL
config cyberchef_url string CyberChef URL
dump enable boolean Enable process dumping/IAT rebuilding in IDA
dump recalculate_pe_checksum boolean Recalculate PE header checksum (slow!)

Location

Type OS Path
Application Windows %TEMP%pe_tree.ini
Application Linux/Mac /tmp/pe_tree.ini
IDAPython Windows %APPDATA%HexRaysIDA Prope_tree.ini
IDAPython Linux/Mac ~/.idapro/pe_tree.ini

3rd party data sharing
The following information will be shared with 3rd party web-applications (depending on configuration) under the following conditions:

VirusTotal
If the VirusTotal URL is specified in the configuration then metadata such as file hashes, timestamps, etc will be sent to VirusTotal for processing when the user clicks on highlighted links or selects “VirusTotal search” from the right-click context menu.

CyberChef
If the CyberChef URL is present in the configuration then any file data will be base64 encoded and sent to CyberChef for processing when the user selects “CyberChef” from the right-click context menu.

Troubleshooting

AttributeError: module ‘pip’ has no attribute ‘main’
or

PyQt5 fails to install under Linux
Try to upgrade pip to version 20.0+:

$ pip install --upgrade pip

ModuleNotFoundError: No module named ‘PyQt5.sip’
Try uninstalling and reinstalling PyQt5 as follows:

pip uninstall PyQt5
pip uninstall PyQt5-sip
pip install PyQt5 PyQt5-sip

Missing imports after dumping
Ensure IDA has found and disassembled all code:
Options -> General -> Analysis -> Reanalyze program
After this is completed try to dump/rebuild imports again.

Contributing
Please feel free to contribute! Issues and pull requests are most welcome.

Developer documentation
To build documentation from source using Sphinx:

$ pip install sphinx
$ sphinx-apidoc -o ./doc/source/ .
$ sphinx-build -b html ./doc/source ./doc/build -E

To view the documentation open ./doc/build/index.html in a web-browser.

 


About the author

Mazen Elzanaty

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