PyExfil

Stress Testing Detection & Creativity

PyExfil was born as a PoC and kind of a playground and grew to be something a bit more. In my eyes it's still a messy PoC that needs a lot more work and testing to become stable. The purpose of PyExfil is to set as many exfiltration, and now also communication, techniques that CAN be used by various threat actors/malware around to bypass various detection and mitigation tools and techniques. You can track changes at the official GitHub page.

Putting it simply, it's meant to be used as a testing tool rather than an actual Red Teaming tool. Although most techniques and methods should be easily ported and compiled to various operating systems, some stable some experimental, the transmission mechanism should be stable on all techniques. Clone it, deploy on a node in your organization and see which systems can catch which techniques.

Getting Started

PIP

For using pip (not necessarily the most updated):

pip install --user PyExfil

Prerequisites

For source:

git clone https://www.github.com/ytisf/PyExfil
cd PyExfil
pip install --user -r requirements.txt

We recommend installing py2exe as well so that you may cross compile various modules to a binary for easier transportation. You can do that with:

pip install py2exe

Installing

Go to the same folder where PyExfil was cloned to and:

pip setup.py --user install

List of Techniques

• Network
  • DNS query
  • HTTP Cookie
  • ICMP (8)
  • NTP Body
  • BGP Open
  • HTTPS Replace Certificate
  • QUIC - No Certificate
  • Slack Exfiltration
  • POP3 Authentication (as password) - Idea thanks to Itzik Kotler
  • FTP MKDIR - Idea thanks to Itzik Kotler
  • Source IP-based Exfiltration
  • HTTP Response
  • IMAP_Draft
• Communication
  • NTP Request
  • DropBox LSP (Broadcast or Unicast)
  • DNS over TLS
  • ARP Broadcast
  • JetDirect
  • GQUIC - Google Quick UDP Internet Connections (Client Hello)
  • MDNS Query - Can be used as broadcast.
  • AllJoyn. Name Service Protocol (IoT discovery) Version 0 ISAT.
  • PacketSize. Using size of packet rather than actual data.
  • UDP-Source-Port Using the source port in UDP as a transmission medium.
  • CertExchange Leveraging certificate exchange function for short bursts of communication.
  • DNSQ Leveraging DNS Queries for communication.
• Physical
  • Audio - No listener.
  • QR Codes
  • WiFi - On Payload
  • 3.5mm Jack
• Steganography
  • Binary Offset
  • Video Transcript to Dictionary
  • Braille Text Document
  • PNG Transparency
  • ZIPCeption
  • DataMatrix over LSB

For usage per modules have a look at the USAGE file.

Data Generation

Although this tool was initially created as a game and later on turned to be a Red Team oriented tool, at the end of a day a major usage of PyExfil is to test various DLP (Data Leakage Protection) systems as well as detection of intrusion. To make the latter mission simpler we have created a little module to generate fake data with a structure that matches both PII and PCI data sets. These are intended to trigger alerts while being broadcate outside of the network.

Here is how to use it:

from pyexfil.includes import CreateTestData

c = CreateTestData(rows=1000, output_location="/tmp/list.csv")
c.Run()

After this you can use which ever PyExfil module you would like to try and exfiltrate the data set created. This way you can test your detection without risking exfiltrating valuable data.

Contributions

We welcome it! From testing, to improving quality of code and up to entirely new methods.

Future Changes

Versioning

For details about version look at the tags on this repository.

Version 1.0.0!

• Surprise on restructure (Add Another).
• Split DOCUMENTATION.md and README.md to two different files.
• Get a nice logo.
• Uniform calling convention for newer modules.
• Exfiltration data-set generator (PII&PCI).

Version 1.3 - Harpax:

• Adding 4 new modules.
• General fixups.
• Some old modules recoded to fit new standard.
• Full compatibility between Python2 and Python3.

Version 1.4 - ?:

• Expand physical exfiltration channels.
• Re-test servers on older modules.
• Add file manipulation class (for example, module zipception does not fit into any existing category although currently residing under Stega).

Hopefully - Close Future

• Attempt at creating a more uniform call convention. See DOCUMENTATION.md.
• Fix that poorly written setup.py.
• Backport all old modules to new calling convention.

In the Distant Future - The Year 2000

• Add Golang/C++ support for portability.
• Extensive testing for py2exe support.

Acknowledgments

People & Companies

• Big shout out to JetBrains!!!
• Thanks to barachy and AM for ideas on protocols to use.
• Thanks to Itzik Kotler for some ideas.
• Shout out to @cac0ns3c for resolving some dependency hell.
• Thanks to @Nilesh0301 for pointing out some Python compatibility issues.
• Big thanks to @hbmartin for pointing us to pytube3 latest update and support.

Resources

• Thanks Wireshark for your awesome wiki and tool. Especially packet dumps.
• Shout out to the nmap guys.
• Thanks to Trey Hunner for the package names.
• The Faker package.
• Special thanks to Thomas Baruchel and Fredrik de Vibe for the txt2pdf package we used in the braille exfiltration package.