P4wnP1 by MaMe82

P4wnP1 is a highly customizable USB attack platform, based on a low cost Raspberry Pi Zero or Raspberry Pi Zero W (required for HID backdoor).

Important

The successor of P4wnP1 is called P4wnP1 A.L.O.A. and hosted here: https://github.com/mame82/P4wnP1_aloa

This repo isn't really suspended, but I'm using all of my time to work on P4wnP1's successor. The new Repo is still private, but information on progress are published via twitter, from time to time (@P4wnP1 or @MaMe82).

More important: Don't waste your time following complicated install instructions: A ready-to-go image of latest P4wnP1 version could be found on the release page: https://github.com/mame82/P4wnP1/releases (seems some of you missed it).

TL;TR

Official WiKi started by @jcstill and @Swiftb0y

There isn't a short summary of this README. If you want to handle this nice tool, I'm afraid you have to read this.

The most important sections:

• Windows LockPicker
• HID covert channel frontdoor
• HID covert channel backdoor (this is the new main feature)
• Getting started section

Introduction

Since the initial release in February 2017, P4wnP1 has come a long way. Today advanced features are merged back into the master branch, among others:

• the Windows LockPicker (unlock Windows boxes with weak passwords, fully automated by attaching P4wnP1)
• the HID covert channel backdoor (Get remote shell access on air gapped Windows targets tunneled only through HID devices, relayed to a WiFi hotspot with SSH access with a Pi Zero W. The target doesn't see a network adapter, serial or any other communication device.)
• the HID covert channel frontdoor (Get access to a python shell on P4wnP1 from a restricted Windows host, tunneled through a raw HID device with low footprint. The target doesn't see a network adapter, serial or any other communication device.)
• refined USB, modular USB setup

External Resources using P4wnP1

• Dan The IOT Man, Introduction + Install instructions "P4wnP1 – The Pi Zero based USB attack-Platform": Dan the IOT Man
• Black Hat Sessions XV, workshop material "Weaponizing the Raspberry Pi Zero" (Workshop material + slides): BHSXV
• ihacklabs[dot]com, tutorial "Red Team Arsenal – Hardware :: P4wnp1 Walkthrough" (Spanish): part 1, part 2, part 3

P4wnP1 Features (quick summary)

• WiFi Hotspot for SSH access (Pi Zero W only), support for hidden ESSID
• operate WiFi in client mode (Pi Zero W only), to relay USB network attacks through WiFi with internet access (MitM)
• the USB device features work in every possible combination with Windows Plug and Play support (class drivers)
• Support for device types
  • HID covert channel communication device (see sections 'HID covert channel frontdoor' and 'HID covert channel backdoor')
  • HID Keyboard
  • USB Mass storage (currently only in demo setup with 128 Megabyte drive)
  • RNDIS (Windows Networking)
  • CDC ECM (MacOS / Linux Networking)
• Raspberry Pi LED state feedback with a simple bash command (led_blink)
• customizable bash based payload scripts (see payloads/ subfolder for examples)
• includes Responder and a precompiled John the Ripper Jumbo version
• Auto attack: P4wnP1 automatically boots to standard shell if an OTG adapter is attached, the current payload only runs if P4wnP1 is connected as USB device to a target (without USB OTG adapter)

Payload descritions and video demos of included payloads

As it is a flexible framework, P4wnP1 allows to develop custom payloads only limited by the imagination of the pentester using it. To get a basic idea some payloads are already included and described here:

Payload: Windows LockPicker

This payload extends the "Snagging creds from locked machine" approach, presented by Mubix (see credits), to its obvious successor:

P4wnP1 LockPicker cracks grabbed hashes and unlocks the target on success, using its keyboard capabilities. This happens fully automated, without further user interaction.

Video demo

I'm still no video producer, so maybe somebody feels called upon to do a demo. Here's my (sh**ty) attempt:

Here's a version of someone doing this much better, thanks @Seytonic

Attack chain (short summary):

1. The USB network interface of P4wnP1 is used to bring up a DHCP which provides its configuration to the target client.
2. Among other options, a WPAD entry is placed and static routes for the whole IPv4 address space are deployed to the target.
3. P4wnP1 redirects traffic dedicated to remote hosts to itself using different techniques.
4. Requests for various protocols originating from the target, are fetched by "Responder.py", which forces authentication and tries to steal the hashes used for authentication.
5. If a hash is grabbed, P4wnP1 LED blinks three times in sequence, to signal that you can unplug and walk away with the hashes for offline cracking. Or...
6. ... you leave P4wnP1 plugged and the hashes are handed over to John the Ripper, which tries to bruteforce the captured hash.
7. If the ´password of the user who locked the box is weakly chosen, chances are high that John the Ripper will be able to crack it, which leads to...
8. ... P4wnP1 ultimately enters the password, in order to unlock the box and you're able to access the box (the cracked password is stored in collected folder, along with the hashes).

The payload Win10_LockPicker.txt has to be chosen in setup.cfg to carry out the attack. It is important to modify the payloads "lang" parameter to your target's language. If you attach a HDMI monitor to P4wnP1, you could watch the status output of the attack (including captured hash and plain creds, if you made it this far).

Payload: Stealing Browser credentials (hakin9_tutorial)

This payload runs a PowerShell script, typed out via P4wnP1's built-in keyboard, in order to dump stored credentials of Microsoft Edge or Internet Explorer. Fetched credentials are stored to P4wnP1's flashdrive (USB Mass Storage). As the name implies, this payload is the result of an hakin9 article on payload development for P4wnP1, which is yet unpublished. For this reason, the payload has RNDIS enabled, although not needed to carry out the attack. Its main purpose is to show how to store the result from a keyboard based attack, to P4wnP1's flashdrive, although the drive letter is only known at runtime of the payload.

Video demo

Backdooring Windows Lock Screen

This payload plants a backdoor which allows to access a command shell with SYSTEM level privileges from the Windows Lockscreen. Once planted, the shell is triggered by sticky keys.

The payload itself is purely keyboard based. The widely known approach to achieve the payloads's goal, is to replace the sethc.exe file. Anyway, this payload does the change based on a registry hack (Debugger property of Image execution options). This means the attack is less noisy, as the filesystem doesn't get touched directly. Additionally the payload shows how to use P4wnP1's keyboard triggers. Pressing NUMLOCK multiple times plants the backdoor, while pressing SCROLLLOCK multiple times removes the backdoor again. Last but not least, the attack demoes a simple UAC bypass, as the PowerShell session used has to be ran with elevated privileges.

The attack requires an unlocked target run by an Administrator account.

The payload demoed here isn't published yet.

Video demo

Payload: HID covert channel frontdoor

Video demo

HID frontdoor features

• Plug and Play install of HID device on Windows (tested on Windows 7 and Windows 10)
• Covert channel based on a raw HID device
• Pure in memory PowerShell payload - nothing is written to disk
• Synchronous data transfer with about 32KBytes/s (fast enough for shells and small file transfers)
• Custom protocol stack to handle HID communication and deal with HID data fragmentation
• HID based file transfer from P4wnP1 to target memory
• Stage 0: P4wnP1 sits and waits, till the attacker triggers the payload stage 1 (frequently pressing NUMLOCK)
• Stage 1: payload with "user space driver" for HID covert channel communication protocols is typed out to the target via USB keyboard
• Stage 2: Communications switches to HID channel and gives access to a custom shell on P4wnP1. This could be used to upload and run PowerShell scripts, which are hosted on P4wnP1, directly into memory of the PowerShell process running on the target. This happens without touching disk or using network communications, at any time.

Payload HID covert channel backdoor (Pi Zero W only)

Video demo

The video is produced by @Seytonic, you should check out his youtube channel with hacking related tutorials and various projects, if you're interested in more stuff like this (link in credits).

@Seytonic thanks for the great tutorial

HID backdoor features

• Payload to bridge an Airgap target, by relaying a shell over raw HID and provide it from P4wnP1 via WiFi
• Plug and Play install of HID device on Windows (tested on Windows 7 and Windows 10)
• Covert channel based on raw HID
• Pure in memory, multi stage payload - nothing is written to disk, small footprint (compared to typical PowerShell IOCs)
• RAT like control server with custom shell:
  • Auto completition for core commands
  • Send keystrokes on demand
  • Excute DuckyScripts (menu driven)
  • Trigger remote backdoor to bring up HID covert channel
  • creation of multiple remote processes (only with covert channel connection)
  • console interaction with managed remote processes (only with covert channel connection)
  • auto kill of remote payload on disconnect
  • shell command to create remote shell (only with covert channel connection)
  • server could be accessed with SSH via WiFi when the hid_backdoor.txt payload is running

HID backdoor attack chain and usage

1. Preparation

• Choose the hid_backdoor.txt payload in setup.cfg (using the interactive USB OTG mode or one of the payloads with SSH network access, like network_only.txt)
• Attach P4wnp1 to the target host (Windows 7 to 10)

2. Access the P4wnP1 backdoor shell

• During boot up, P4wnP1 opens a wireless network called P4wnP1 (password: MaMe82-P4wnP1)
• Connect to the network and SSH in with [email protected]
• If everything went fine, you should be greeted by the interactive P4wnP1 backdoor shell (If not, it is likely that the target hasn't finished loading the USB keyboard drivers). The SSH password is the password of the user pi, which is raspberry in the default configuration.

3. Ad-Hoc keyboard attacks from P4wnP1 backdoor shell (without using the covert channel), could be done from here:

• Entering help shows available commands
• Use the SetKeyboardLayout to set the keyboard layout according to your target's language. This step is important and should always be taken first, otherwise most keyboard based attacks fail.
• to print the current keyboard layout use GetKeyboardLayout. The default keyboard language for the P4wnP1 backdoor shell could be changed in hidtools/backdoor/config.txt
• use the SendKeys command followed by an ASCII key sequence to send keystrokes to the target
• As you will notice, the SendKeys command is somehow restricted, no control keys could be sent, even a RETURN is problematic. So for more complex key sequences the FireDuckyScript command comes to help.
• FireDuckyScript accepts the name of a script residing in the DuckyScript/ folder. The folder is prefilled with some demo scripts. If you omit the script name behind the FireDuckyScript command, you will be presented with a menue to choose a script. If you wonder why one would write a DuckyScript sending an <ALT> + <F4> only, you're thinking in the old world of RubberDucky. With P4wnP1 and its capbility to run DuckyScripts dynamically, such short scripts come in handy. If you don't know what I'm talking about run the P4wnP1_youtube.duck script and you'll know where scripts like AltF4_Return.duck are needed ;-)

So that's all

... no just joking. Four months without commits wouldn't have been passed if there isn't more. Up till here, there was no covert channel communication, right?!

4. Fire stage 1 of the covert channel payload ('FireStage1' command)

• As we are able to print characters to the target, we are able to remotly execute code. P4wnP1 uses this capability to type out a PowerShell script, which builds and executes the covert channel communication stack. This attack works in multiple steps:
  1. Keystrokes are injected to start a PowerShell session and type out stage 1 of the payload. Depending on how the command FireStage1 is used, this happens in different flavours. By default a short stub is executed, which hides the command windows from the user, followed by the stage 1 main script.
  2. The stage 1 main script comes in two fashions:
     • Type 1: A pure PowerShell script which is short and thus fast, but uses the infamous IEX command (this command has the capability to make threat hunters and blue teamers happy). This is the default stage 1 payload.
     • Type 2: A dot NET assembly, which is loaded and executed via PowerShell. This stage 1 payload takes longer to execute, as more characters are needed. But, as you may already know, it doesn't use the IEX command.
• It is worth mentioning, that the PowerShell session is started without command line arguments, so there's nothing which triggers detection mechanisms for malicious command lines. Theres no parameter like -exec bypass, -enc, -NoProfile or hidden ... nothing suspicious! The shortcoming is, that we need to wait till the PowerShell window opens before typing is continued. As we are not able to detect for input readiness and there are boxes which take years to bring up an interactive PowerShell window, the delay between running powershell.exe and starting of stage1 typeout could be changed with the second parameter to the FireStage1 command (default is 1000 milliseconds).
• Last but not least, if you append nohide to the end of the FireStage1 command line, the Window hiding stub isn't executed in upfront and you should be able to see all my sh**ty debug output.

5. Loading stage 2

• There's no rocket sience here. The stage 1 payload initializes the basic interface to the custom HID device and receives stage 2 fully automated. Stage 2 includes all the protocol layers and the final backdoor. It gets directly loaded into memory as dot NET assembly.
• So why dot NET ? The early versions of the backdoor have been fully developed in PowerShell. This resulted in a big mess when it comes to multi threading, PS 2.0 compatability without class inheritance and multi thread debugging with ISE. I don't want to say that is impossible (if you watched the commit history, there's the proof that it is possible), but there's no benefit. To be precise, there are disadvantages: Much more code is needed to achieve the same, the code is slower and PowerShell Module Logging would be able to catch every single script command from the payload. In contrast to using a dot NET assembly, where the only PowerShell commands which could get logged, are the ones which load the assembly and run the stage 2 trigger. Everything else is gone as soon as the payload quits. So ... small footprint, yeah.
• But don't get "PowerShell inline assemlies" compiled to a temporary file on disk ?!?! Yes, they do! At least if they're written with CSharp inline code. Luckily P4wnP1 doesn't do this. The assemblies are shipped pre-compiled.

6. Using the backdoor connection

• After stage 2 has successfully ran, the prompt of the P4wnP1 backdoor shell should indicate a client connection.
• From here on, new commands are usable, these include:
  • CreateProcess
  • interact
  • KillProcess
  • KillClient
  • and ... :-) ... shell
• I'm too tired to explain these here, but I guess you'll find it out.

HID backdoor attack - summary

1. Choose hid_backdoor.txt payload
2. Connect P4wnP1 device to Windows target
3. Connect to the newly spawned P4wnP1 WiFi with a different device (could be a smartphone, as long as a SSH client is installed)
4. Set the correct target keyboard layout with SetKeyboardLayout (or alter hidtools/backdoor/config.txt)
5. On the P4wnP1 shell run SendKeys or FireDuckyScript to inject key strokes
6. To fire up the covert channel HID backdoor, issue the command FireStage1
7. After the target connected back, enter shell to create a remote shell through the covert channel

HID backdoor - Currently missing features

• File transfer implementation (upload / download) ... but hey... you guys are redteamers and pentesters! You know how to deal with non-interactive remote shells, right? If not go and take an OSCP or something like that, but don't bother me with a feature request for this. Update: File transfer for HID backdoor is implented wit the commands upload and download - so files are move back and forth through a raw HID device now between P4wnP1 and the target, now
• Run TCP sockets through the HID channel. Yes, it would be really nice to have a SOCKS4a or SOCKS5 listening on P4wnP1, tunneling comms through the target client. I'm not sure when this will get done, as this PoC project consumed far too much time. But hey, the underlying communication layers are prepared to handle multiple channels and as far as I know, you're staring at the source code, right now!

P4wnP1 more advanced features (excerpt)

Advanced HID Keyboard Features

• Keyboard payloads could be triggered by targets main keyboard LEDs (NUMLOCK, CAPSLOCK and SCROLLLOCK)
• dynamic payload branching based on LED triggers
• Supports DuckyScript (see hid_keyboard2.txt payload for an advanced example)
• Supports raw ASCII Output via HID Keyboard (could be used to print out character based files via keyboard, like cat /var/log syslog | outhid)
• Multi Keyboard language layout support (no need to worry about target language when using HID commands)
• Output starts when target keyboard driver is loaded (no need for manual delays, onKeyboardUp callback could be used in payloads)

Advanced Network Features

• Fake RNDIS network interface speed up to 20GB/s to get the lowest metric and win every fight for the dominating 'default gateway' entry in routing tables, while carrying out network attacks (patch could be found here and the README here)
• Automatic link detection and interface switching, if a payload enables both RNDIS and ECM network
• SSH server is running by default, so P4wnP1 could be connected on 172.16.0.1 (as long as the payload enables RNDIS, CDC ECM or both) or on 172.24.0.1 via WiFi
• if both, WiFi client mode and WiFi Access Point mode, are enabled - P4wnP1 fails over to open an Access Point in case the target WiFi isn't reachable (Pi Zero W only)

Advanced payload features

• bash payloads based on callbacks (see template.txt payload for details)
  • onNetworkUp (when target host gets network link active)
  • onTargetGotIP (if the target received an IP, the IP could be accessed from the payload script)
  • onKeyboardUp (when keyboard driver installation on target has finished and keyboard is usable)
  • onLogin (when a user logs in to P4wnP1 via SSH)
• configuration can be done globally (setup.cfg) or overwritten per payload (if the same parameter is defined in the payload script)
• settings include:
  • USB config (Vendor ID, Product ID, device types to enable ...)
  • WiFi config (SSID, password ...)
  • HID keyboard config (target keyboard language etc.)
  • Network and DHCP config
  • Payload Selection

Feature Comparison with BashBunny

Some days after initial P4wnP1 commit, Hak5's BashBunny was announced (and ordered by myself). Here's a little feature comparison:

SumUp: BashBunny is directed to easy usage, but costs 20 times as much as the basic P4wnP1 hardware. P4wnP1 is directed to a more advanced user, but allows outbound communication on a separate network interface (routing and MitM traffic to upstream internet, hardware backdoor etc.)

Install instructions

Refer to INSTALL.md (outdated, will be rewritten someday)

Getting started

The default payload (payloads/network_only.txt) makes th Pi accessible via Ethernet over USB and WiFi. You could SSH into P4wnP1

via USB

[email protected]

or via WiFi

[email protected]
Network name: P4wnP1
Key: MaMe82-P4wnP1

From there you could alter setup.cfg to change the current payload (PAYLOAD parameter) and keyboard language (LANG parameter).

Caution: If the chosen payload overwites the global LANG parameter (like the hid_keyboard demo payloads), you have to change the LANG parameter in the payload, too. If your remove the LANG parameter from the payload, the setting from setup.cfg is taken. In short words, settings in payloads have higher priority than settings in setup.cfg

Requirements

• Raspberry Pi Zero / Pi Zero W (other Pis don’t support USB gadget because they’re equipped with a Hub, so don’t ask)
• Raspbian Jessie/Stretch Lite pre installed (kernel is updated by the P4wnP1 installer, as the current kernel has errors in the USB gadget modules, resulting in a crash)
• Internet connection to run the install.sh script
• the project is still work in progress, so features and new payloads are added in frequently (make sure to have an updated copy of P4wnP1 repo)

Snagging creds from locked machines, vulnerable application (Oracle JAVA JRE/JDK vuln)

During tests of P4wnP1 a product has been found to answer NTLM authentication requests on wpad.dat on a locked and fully patched Windows 10 machine. The NTLM hash of the logged in user is sent by a third party software, even if the machine isn’t domain joined. The flaw has been reported to the respective vendor. Details will be added to the readme as soon as a patch is available. For now I’ll recently update the disclosure timeline here.

Disclosure Timeline discovered NTLM hash leak:

So here we are now. The vulnerable product has been the Oracle Java JRE and JDK (1.7 Update 141 and 1.8 Update 131). The issue has been fixed with the "Oracle Critical Patch Update Advisory - July 2017", which could be found here. So go and update your Java JRE/JDK.

Credits to

• Seytonic (youtube channel on hacking and hardware projects: Seytonic
• Rogan Dawes (sensepost, core developer of Universal Serial Abuse - USaBUSe): USaBUSe
• Samy Kamkar: PoisonTap
• Rob ‘MUBIX’ Fuller: “Snagging creds from locked machines” and MUBIX at github
• Laurent Gaffie (lgandx): Responder
• Darren Kitchen (hak5darren): DuckEncoder, time to implement a WiFi capable successor for BashBunny ;-)