DuckyScript™ Quick Reference

DuckyScript™ is the programming language of the USB Rubber Ducky™, Hak5® hotplug attack gear and officially licensed devices (Trademark Hak5 LLC. Copyright © 2010 Hak5 LLC. All rights reserved.)

Shop Compatible Devices
DuckyScript™ Version
Device Compatibility

1.0

Original USB Rubber Ducky (USB-A Only)

3.0

New USB Rubber Ducky (USB-A & USB-C)

Hak5 Payload Hub - Featured Payloads & home of the Hak5 Payload Awards
Contribute and browse payloads on GitHub
Take your DuckyScript™ payloads to the next level with this full-featured, web-based development environment.

The REM command does not perform any keystroke injection functions. REM gets its name from the word remark. While REM may be used to add vertical spacing within a payload, blank lines are also acceptable and will not be processed by the compiler.

Defining a comment block is simple! Start the comment with REM_BLOCK and end the comment with END_REM; everything in between will be considered a comment without the need to prepend every new line with REM. Comment blocks can be especially useful when you have multiple lines to be included in a single comment or want to retain formatting.

The STRING command keystroke injects (types) a series of keystrokes. STRING will automatically interpret uppercase letters by holding the SHIFT modifier key where necessary. The STRING command will also automatically press the SPACE cursor key, however trailing spaces will be omitted.

The STRINGLN command, like STRING, will inject a series of keystrokes then terminate with a carriage return (ENTER).

STRING blocks can be used effectively to convert multiple lines into one without needing to prepend each line with STRING

is the equivalent of

Or in this case: STRING abc

STRINGLN blocks can be used like here-doc; allowing you to inject multiple lines as they are written in the payload.

is the equivalent of

Result

Deploying this payload will produce the following keystroke injection on the target machine:

The cursor keys are used to navigate the cursor to a different position on the screen.

UP DOWN LEFT RIGHT

UPARROW DOWNARROW LEFTARROW RIGHTARROW

PAGEUP PAGEDOWN HOME END

INSERT DELETE DEL BACKSPACE

TAB

SPACE

System keys are primarily used by the operating system for special functions and may be used to interact with both text areas and navigating the user interface.

ENTER

ESCAPE

PAUSE BREAK

PRINTSCREEN

MENU APP

F1 F2 F3 F4 F5 F6 F7 F8 F9 F0 F11 F12

Modifier keys held in combination with another key to perform a special function. Common keyboard combinations for the PC include the familiar CTRL c for copy, CTRL x for cut, and CTRL v for paste.

SHIFT

ALT

CONTROL or CTRL

COMMAND

WINDOWS or GUI

In addition to the basic modifier key combinations, such as CTRL c, modifiers and keys may be combined arbitrarily.

CTRL SHIFT

ALT SHIFT

COMMAND CTRL

COMMAND CTRL SHIFT

COMMAND OPTION

COMMAND OPTION SHIFT

CONTROL ALT DELETE

Injecting a modifier key alone without another key — such as pressing the WINDOWS key — may be achieved by prepending the modifier key with the INJECT_MOD command.

Lock keys toggle the lock state (on or off) and typically change the interpretation of subsequent keypresses. For example, caps lock generally makes all subsequent letter keys appear in uppercase.

CAPSLOCK

NUMLOCK

SCROLLOCK

The DELAY command instructs the USB Rubber Ducky to momentarily pause execution of the payload. This is useful when deploying a payload which must "wait" for an element — such as a window — to load. The DELAY command accepts the time parameter in milliseconds.

The DELAY command may also accept an integer variable.

By default, if no other button command is currently in use, pressing the button during payload execution will make the USB Rubber Ducky stop any further keystroke injection. It will then become an ordinary USB flash drive, commonly referred to as "arming mode".

Halts payload execution until a button press is detected. When this command is reached in the payload, no further execution will occur.

The BUTTON_DEF command defines a function which will execute when the button is pressed anytime within the payload so long as the button control is not already in use by the WAIT_FOR_BUTTON_PRESS command or other such function.

The DISABLE_BUTTON command prevents the button from calling the BUTTON_DEF.

The ENABLE_BUTTON command allows pressing the button to call the BUTTON_DEF.

The USB Rubber Ducky includes an LED which may be helpful when deploying certain payloads where feedback is important.

The LED_OFF command will disable all LED modes.

The LED_R command will enable the red LED.

The LED_G command will enable the green LED.

An attack mode is the device type that a USB Rubber Ducky, is functioning as or emulating. If no ATTACKMODE command is specified as the first command (excluding REM), the HID attack mode will execute, allowing the device to function as a keyboard. The ATTACKMODE command may be run multiple times within a payload, which may cause the device to be re-enumerated by the target if the attack mode changes.

Required Parameters

ATTACKMODE Parameter
Description

HID

Functions as a Human Interface Device, or Keyboard, for keystroke injection.

STORAGE

Functions as USB Mass Storage, or a Flash Drive, for copying files to/from the target.

HID STORAGE

Functions as both USB Mass Storage and Human Interface Device

OFF

Will not function as any device. May be used to disconnect the device from the target.

Optional Parameters

When using these optional parameters, VID and PID must be used as a set. Further, MAN, PROD and SERIAL must also be used as a set.

ATTACKMODE Parameter
Description

VID_

Vendor ID (16-bit HEX)

PID_

Product ID (16-bit HEX)

MAN_

Manufacturer (32 alphanumeric characters)

PROD_

Product (32 alphanumeric characters)

SERIAL_

Serial (12 digits)

The SAVE_ATTACKMODE command will save the currently running ATTACKMODE state (including any specified VID, PID, MAN, PROD and SERIAL parameters) such that it may be later restored.

The RESTORE_ATTACKMODE command will restore a previously saved ATTACKMODE state.

The DEFINE command is used to define a constant. One may consider the use of a DEFINE within a payload like a find-and-replace at time of compile.

The VAR command will initiate a variable. Unlike constants, variables begin with a dollar sign ("$"). Variables contain unsigned integers with values from 0 to 65535. Booleans may be represented as well, either by TRUE/FALE or any non-zero number and 0 respectively.

Operators instruct the payload to perform a given mathematical, relational or logical operation.

Operator
Meaning

=

Assignment

+

Add

-

Subtract

*

Multiply

/

Divide

%

Modulus

^

Exponent

Will compare two values to evaluate a single boolean value.

Operator
Meaning

==

Equal to

!=

Not equal to

>

Greater than

<

Less than

>=

Greater than or equal to

<=

Less than or equal to

Parentheses ( ) are required to define the precedence conventions.

Logical operators may be used to connect two or more expressions.

Operator
Description

&&

Logical AND. If both the operands are non-zero, the condition is TRUE.

||

Logical OR. If any of the two operands is non-zero, the condition is TRUE.

When assigning a value to a variable, the variable itself may be referenced.

Operate on the uint16 values at the binary level.

Operator
Description

&

Bitwise AND. If the corresponding bits of the two operands is 1, will result in 1. Otherwise if either bit of an operand is 0, the result of the corresponding bit is evaluated as 0.

|

Bitwise OR. If at least one corresponding bit of the two operands is 1, will result in 1.

>>

Right Shift. Accepts two numbers. Right shifts the bits of the first operand. The second operand determines the number of places to shift.

<<

Left Shift. Accepts two numbers. Left shifts the bits of the first operand. The second operand decides the number of places to shift.

Conditional statements, loops and functions allow for dynamic execution.

The flow control statement IF will determine whether or not to execute its block of code based on the evaluation of an expression. One way to interpret an IF statement is to read it as "IF this condition is true, THEN do this".

The ELSE statement is an optional component of the IF statement which will only execute when the IF statement condition is FALSE.

Loops are flow control statements that can be used to repeat instructions until a specific condition is reached.

The block of code within the WHILE statement will continue to repeatedly execute for a number of times (called iterations) for as long as the condition of the WHILE statement is TRUE.

Functions are blocks of organized single-task code that let you more efficiently run the same code multiple times without the need to copy and paste large blocks of code over and over again.

A function may return a integer or boolean value which may also be evaluated.

The pseudorandom number generator provides randomization for keystroke injection, variables and attackmode parameters. The first time a randomization feature is used, a seed.bin will be generated on the root of the MicroSD card. One may also be generated from the Hak5 IDE.

Command
Character Set

RANDOM_LOWERCASE_LETTER

abcdefghijklmnopqrstuvwxyz

RANDOM_UPPERCASE_LETTER

ABCDEFGHIJKLMNOPQRSTUVWXYZ

RANDOM_LETTER

abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ

RANDOM_NUMBER

0123456789

RANDOM_SPECIAL

!@#$%^&*()

RANDOM_CHAR

abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 0123456789 !@#$%^&*()

The internal variable $_RANDOM_INT assigns a random integer between the specified $_RANDOM_MIN and $_RANDOM_MAX values. May be 0-65535. The default values are 0-9.

The ATTACKMODE command may accept random values for the optional parameters.

ATTACKMODE Parameter
Result

VID_RANDOM

Random Vendor ID

PID_RANDOM

Random Product ID

MAN_RANDOM

Random 12 alphanumeric character iManufacturer

PROD_RANDOM

Random 12 alphanumeric character iProduct

SERIAL_RANDOM

Random 12 digit serial number

A key may be held, rather than pressed, by specifying a HOLD and RELEASE command with a DELAY in between the two. Both HOLD and RELEASE must specify a key. Multiple simultaneous keys may be held.

These simple commands exist to control the execution of a payload.

The RESTART_PAYLOAD command ceases execution, restarting the payload from the beginning.

The STOP_PAYLOAD command ceases and further execution.

The RESET command clears the keystroke buffer, useful for debugging complex hold key states.

Jitter randomly varies the delay between individual key presses based on the seed.bin value.

Internal Variable
Description

$_JITTER_ENABLED

Set TRUE to enable and FALSE to disable jitter.

$_JITTER_MAX

Integer (0-65535) of maximum time in milliseconds between keystrokes. Default 20.

The inject.bin and seed.bin file may be hidden from the MicroSD card before implementing ATTACKMODE STORAGE. The HIDE_PAYLOAD and RESTORE_PAYLOAD commands must be run while using ATTACKMODE OFF or ATTACKMODE HID.

Hides the inject.bin and seed.bin files from the MicroSD card.

Restores the inject.bin and seed.bin files to the MicroSD card.

USB HID devices contain both IN endpoints for data (keystrokes) from the keyboard to computer, and OUT endpoints for data (LED states) from the computer to the keyboard. In many cases the LED state control codes sent from the computer to the attached keyboard are sent to all attached "keyboards". Versions of macOS behave differently.

Command
Description

WAIT_FOR_CAPS_ON

Pause until caps lock is turned on

WAIT_FOR_CAPS_OFF

Pause until caps lock is turned off

WAIT_FOR_CAPS_CHANGE

Pause until caps lock is toggled on or off

WAIT_FOR_NUM_ON

Pause until num lock is turned on

WAIT_FOR_NUM_OFF

Pause until num lock is turned off

WAIT_FOR_NUM_CHANGE

Pause until num lock is toggled on or off

WAIT_FOR_SCROLL_ON

Pause until scroll lock is turned on

WAIT_FOR_SCROLL_OFF

Pause until scroll lock is turned off

WAIT_FOR_SCROLL_CHANGE

Pause until scroll lock is toggled on or off

The currently reported lock key states may be saved and later recalled using the SAVE_HOST_KEYBOARD_LOCK_STATE and RESTORE_HOST_KEYBOARD_LOCK_STATE commands.

Exfiltration is the unauthorized transfer of information from a system. Typically performed over a physical medium (copying to a USB flash disk such as the USB Rubber Ducky while using ATTACKMODE STORAGE) or a network medium such as email, ftp, smb, http, etc.

Physical Exfiltration Example

Network Exfiltration Example

By taking advantage of the HID OUT endpoint as described in the lock keys section, binary data may be exfiltrated "out of band" using the Keystroke Reflection side-channel attack. This is done by using the $_EXFIL_MODE_ENABLED internal variable. The reflected lock keystrokes are saved to loot.bin on the root of the MicroSD card. For a detailed example, see the section on Keystroke Reflection.

Similarly, arbitrary variable data may be saved to the loot.bin file using the EXFIL command.

Internal Variables

Internal Variable
Description

BUTTON

$_BUTTON_ENABLED

Returns TRUE if the button is enabled or FALSE if the button is disabled.

$_BUTTON_USER_DEFINED

Returns TRUE if a BUTTON_DEF has been implemented in the payload or FALSE if it hasn't been implemented.

$_BUTTON_PUSH_RECEIVED

Returns TRUE if the button has ever been pressed. May be retrieved or set.

$_BUTTON_TIMEOUT

The button debounce, or cooldown time before counting the next button press, in milliseconds. The default value is 1000.

LED

$_SYSTEM_LEDS_ENABLED

Default set TRUE. May be retrieved or set. Boot and ATTACKMODE change LED.

$_STORAGE_LEDS_ENABLED

Default set TRUE. May be retrieved or set.

Blinks the LED red/green on storage read/write in ATTACKMODE STORAGE.

$_LED_CONTINUOUS_SHOW_STORAGE_ACTIVITY

Default set TRUE. May be retrieved or set.

The LED will light solid green when the storage has been inactive for longer than $_STORAGE_ACTIVITY_TIMEOUT (default 1000 ms). Otherwise, the LED will light red when active.

$_INJECTING_LEDS_ENABLED

Default set TRUE. May be retrieved or set. When TRUE the LED will blink green on payload execution.

$_EXFIL_LEDS_ENABLED

Default set TRUE. May be retrieved or set. When TRUE the LED will blink green during Keystroke Reflection.

$_LED_SHOW_CAPS

Default set FALSE. May be retrieved or set. When TRUE will bind the GREEN LED state to the CAPSLOCK state.

$_LED_SHOW_NUM

Default set FALSE. May be retrieved or set. When TRUE will bind the RED LED state to the NUMLOCK state.

$_LED_SHOW_SCROLL

Default set FALSE. May be retrieved or set. When TRUE will bind the GREEN LED state to the SCROLLLOCK state.

ATTACKMODE

$_CURRENT_VID

Returns the currently operating Vendor ID with endian swapped. May only be retrieved. Cannot be set.

$_CURRENT_PID

Returns the currently operating Product ID with endian swapped. May only be retrieved. Cannot be set.

$_CURRENT_ATTACKMODE

Returns the currently operating ATTACKMODE represented as 0 for OFF, 1 for HID, 2 for STORAGE and 3 for both HID and STORAGE

RANDOM

$_RANDOM_INT

Random integer within set range.

$_RANDOM_MIN

Random integer minimum range (unsigned, 0-65535)

$_RANDOM_MAX

Random integer maximum range (unsigned, 0-65535)

$_RANDOM_SEED

Random seed from seed.bin

$_RANDOM_LOWER_LETTER_KEYCODE

Returns random lower letter scancode (a-z)

$_RANDOM_UPPER_LETTER_KEYCODE

Returns random upper letter scancode (A-Z)

$_RANDOM_LETTER_KEYCODE

Returns random letter scancode (a-zA-Z)

$_RANDOM_NUMBER_KEYCODE

Returns random number scancode (0-9)

$_RANDOM_SPECIAL_KEYCODE

Returns random special char scancode (shift+0-9)

$_RANDOM_CHAR_KEYCODE

Returns random letter number or special scancode

JITTER

$_JITTER_ENABLED

Set TRUE to enable jitter. Default FALSE.

$_JITTER_MAX

Sets the maximum time between key presses in milliseconds. The default maximum is 20 ms.

LOCK KEYS

$_CAPSLOCK_ON

TRUE if on, FALSE if off.

$_NUMLOCK_ON

TRUE if on, FALSE if off.

$_SCROLLLOCK_ON

TRUE if on, FALSE if off.

$_SAVED_CAPSLOCK_ON

On USB attach or SAVE_HOST_KEYBOARD_LOCK_STATE, sets TRUE or FALSE depending on the reported OS condition.

$_SAVED_NUMLOCK_ON

On USB attach or SAVE_HOST_KEYBOARD_LOCK_STATE, sets TRUE or FALSE depending on the reported OS condition.

$_SAVED_SCROLLLOCK_ON

On USB attach or SAVE_HOST_KEYBOARD_LOCK_STATE, sets TRUE or FALSE depending on the reported OS condition.

$_RECEIVED_HOST_LOCK_LED_REPLY

On receipt of any lock state LED control code, sets TRUE. This flag is helpful for fingerprinting certain operating systems (e.g. macOS) or systems which do not reflect lock keys.

STORAGE

$_STORAGE_ACTIVITY_TIMEOUT

As payload is running, this value decrements if storage activity is not detected. Default value is 1000.

EXFILTRATION

$_EXFIL_MODE_ENABLED

Default FALSE. Set TRUE to enable Keystroke Reflection. Will listen for CAPSLOCK and NUMLOCK changes, writing binary values to loot.bin. num=1, caps=0.

OS_DETECT

$_HOST_CONFIGURATION_REQUEST_COUNT

Used by OS_DETECT EXTENSION to detect device enumeration count.

$_OS

Used by OS_DETECT EXTENSION to return value of fingerprinted operating system. May return WINDOWS, MACOS, LINUX, CHROMEOS, ANDROID, IOS. These names are reserved and should not be used in user variables.

Last updated

Was this helpful?