Flipper Zero Explained

Flipper Zero
Flipper Zero
Release Date:August 2020
Cpu:STMicroelectronics STM32WB55
Memory Card:Micro SD (up to 256 GB)
Dimensions:100 x 40 x 25 mm
Weight:104 grams
Os:FreeRTOS

The Flipper Zero is a portable multi-functional device developed for interaction with access control systems.[1] The device is able to read, copy, and emulate RFID and NFC tags, radio remotes, iButton, and digital access keys, along with a GPIO interface.[2] It was first announced in August 2020 through the Kickstarter crowdfunding campaign, which raised $4.8 million.[3] The first devices were delivered to backers 18 months after completion of the crowdfunding campaign. The device's user interface embodies a pixel-art dolphin virtual pet. The interaction with the virtual pet is the device's core game mechanic. The usage of the device's functions defines the appearance and emotions of the pet.[4]

In the built-in game, the main mechanism to "upgrade" the dolphin is to use the various hacking tools. While harmless uses (like as a remote control for a television, or carbon dioxide sensor) exist, some of the built-in tools have potential criminal uses, including RFID skimming, bluetooth spamming (spamming a bluetooth connection, crashing a person's phone), and emulation of RFID chips such as those found in identification badges, using the built-in radio cloner to open garage doors, unlocking cars, and functioning as a wireless BadUSB. The device has been removed for sale from Amazon.com.

Origin

The device was developed by Alex Kulagin and Pavel Zhovner in 2019.[5] They started raising funds on Kickstarter.[5]

Overview

Flipper Zero is designed for interaction with various types of access control systems, radio protocols, RFID, near-field communication (NFC), and infrared signals.[6] [7] To operate the device, it is not required to have a computer or a smartphone; it can be controlled via a 5-position D-pad and a separate back button. Flipper Zero has a monochrome orange backlight LCD screen with a resolution of 128x64 pixels. For connection with external modules, the device has general-purpose input/output (GPIO) pinholes on the top side. User data and firmware updates are stored on a Micro SD card. Some actions, such as firmware or user data update, require a connection to a computer or a smartphone with developer's software installed.

In July 2023 an app store was opened for the device.[8]

Technical specification

The electronic schematics[9] and firmware[10] of the Flipper Zero project are open sourced under the GNU General Public License. At the same time, the device does not fit into the open-source hardware category because the printed circuit boards are not open-sourced, which does not allow enthusiasts to make their own copies of the device without knowledge of electrical engineering.

Hardware

Flipper Zero is based on a dual-core ARM architecture STM32WB55 microcontroller, which has 256 KB of RAM and 1 MB of Flash storage. The first core is a 64 MHz Cortex-M4 which runs the main firmware. The second core is a 32 MHz Cortex-M0 which runs STMicroelectronics proprietary firmware that implements the Bluetooth Low Energy protocol. For radio transmitting and receiving in the 300–900 MHz radio frequency range, a Texas Instruments CC1101[11] chip is used, which supports amplitude-shift keying (ASK) and frequency-shift keying (FSK) modulations. Unlike software-defined radio, the CC1101 chip cannot capture raw radio signals. This limitation requires the user to pre-configure the modulation parameters before receiving a radio signal, otherwise the signal will be received incorrectly.

Hardware expansion

In February 2024 a video game module was released for the Flipper Zero by its makers.[12] The device allows the Flipper to be used as a game controller or connected to a TV and is based around the Raspberry Pi Pico.[12]

Firmware

The Flipper Zero firmware is based on the FreeRTOS operating system, with its own software abstraction over the hardware layer. The firmware is mostly written in the C programming language, with occasional use of C++ in third-party modules. The system uses multitasking in combination with an event-driven architecture to organize the interaction of applications and services executed in a single address space and communicating through a system of queues and events. The system can be executed from both random-access memory (RAM) and read-only memory (ROM). Execution from RAM is used to deliver over-the-air (OTA) firmware updates.

The firmware consists of the following components:

User and system data is stored in built-in flash memory, which is based on the LittleFS library. Interaction with the file system on the SD card is implemented using the FatFs library.

The build system is based on the SCons tool with additional tooling written in Python. For compilation, the system uses its own open toolchain based on GNU Compiler Collection.

Applications

Sub-GHz

Flipper Zero has a built-in module that can read, store, and emulate remote controls, allowing it to receive and send radio frequencies between 300 and 928 MHz. These switches, radio locks, wireless doorbells, remote controls, barriers, gates, smart lighting, and other devices can all be operated with these controls. Using Sub-GHz Flipper Zero can also receive and decode the data from many weather stations.[13]

125 kHz RFID

Flipper Zero is compatible with low-frequency (LF) radio frequency identification (RFID), which is used in supply chain tracking systems, animal chips, and access control systems. LF RFID cards typically don't offer high levels of security, in contrast to NFC cards. Numerous form factors of this technology are available, including plastic cards, key fobs, tags, wristbands, and animal microchips. A low-frequency RFID module in the Flipper Zero can read, save, simulate, and write LF RFID cards.[14]

NFC

NFC technology, which is used in smart cards for access control and cards, and digital business cards, is compatible with Flipper Zero. The 13.56 MHz NFC module has the ability to imitate, read, and store these cards. An NFC card is a transponder with a unique identification (UID), and rewritable memory for data storage. When placed close to a reader, NFC cards transmit the needed data.[15]

Infrared

Flipper Zero can read and transmit signals that use infrared light (IR) such as TVs, air conditioners, or audio devices. It can learn and save infrared remote controls or use its own Universal remotes.[16]

GPIO and Modules

Flipper Zero explores hardware, flash firmware, debugging, and fuzz. It is able to function as a USB converter for UART, SPI, or I2C. The built-in GPIO pins connect to hardware, operate by buttons, send out code, and display messages on the LCD screen.[17]

iButton

The Flipper Zero has an iButton connector to allow it to read and emulate iButton contact keys.[18]

BadUSB

BadUSB devices have the ability to alter system settings, unlock backdoors, recover data, launch reverse shells, and do any other physical access-based actions. Flipper Zero can function as a BadUSB and, when connected to an insecure computing device, acts as a keyboard-like Human interface device (HID). Commands (the payload) are injected and executed using DuckyScript (the macro scripting language developed as part of the 'USB Rubber Ducky' BadUSB project).[19] [20]

U2F (Universal 2nd Factor)

Authenticator

HID controllers

Flipper Zero can replace certain HID (human interface device) controllers. This allows it to interact with your phone or computer. It can remotely control media players, computer keyboards or mouse, presentations, and more.[21]

Bans, seizure and police bulletin

U.S. Customs seizure and release

In late 2022, U.S. Customs and Border Protection seized a shipment of 15,000 devices, but they were eventually released.[22]

Amazon ban

On 7 April 2023, Amazon banned sales of the Flipper Zero via their site for being a "card skimming device".[23] Only WiFi development boards, screen protectors and cases are still available from the site after the ban.[23]

Brazil seizures

In 2023 people in Brazil who ordered Flipper Zeros reported that their orders had been seized by Anatel.[24] According to the Electronic Frontier Foundation, Anatel has flagged the devices as being a tool for criminal purposes, making the certification process complicated.[24] Users have tried getting their devices certified, but to no avail.[24] The EFF has said that the seizures would limit the ability of Brazilian cybersecurity researchers to conduct research, as they have legitimate uses for the device.[24]

Police bulletin on Flipper Zero

In August 2023, The Daily Dot published an article on a bulletin for police officers published by the South Dakota Fusion Centre.[22] The document suggested that extremists might use the device to bypass access control systems controls, particularly on power stations.[22] The bulletin admitted there was no concrete evidence of plans by said extremists to use the device, though they expressed interest in online forums.[22]

Flipper CEO Pavel Zhovner was shown a copy of the bulletin and said that the Flipper Zero had been deliberately designed to not affect modern access control systems.[22] He also pointed out that the bulletin itself said that gates at power stations were not inherently vulnerable to the device but that older gates might be.[22]

Gatwick seizure

On 27 September 2023 a security staff member at Gatwick Airport confiscated a Flipper Zero from Vitor Domingos due to security concerns.[25] The device was then handed over to Sussex Police.[25]

Potential Canadian Ban

In February 2024, Innovation, Science, and Economic Development Canada announced that they had the intention of banning the Flipper Zero and other devices that could be used to clone wireless signals for remote entry in response to a significant increase in auto thefts.[26]

On 20 March 2024, ISED announced that it would ban the use of the Flipper for illegal acts, but not ban it outright.[27]

See also

Notes and References

  1. Web site: Flipper Zero turns hacking into a Tamagotchi-style game . 15 Mar 2022 . . 16 April 2023 . https://web.archive.org/web/20230416185905/https://www.engadget.com/flipper-zero-tamagotchi-hacking-game-175949581.html . live .
  2. Web site: Meet Flipper, the Tamagotchi You Feed by Hacking Stuff. 5 January 2021. Vice. 15 Mar 2022. 15 May 2023. https://web.archive.org/web/20230515140548/https://www.vice.com/en/article/bvxyjm/meet-flipper-the-tamagotchi-you-feed-by-hacking-stuff. live.
  3. Web site: Flipper Zero raising a staggering $4.88 million on a Kickstarter. 2 September 2020. Hackaday. 30 June 2022. 5 June 2023. https://web.archive.org/web/20230605133651/https://hackaday.com/2020/09/02/flipper-zero-blasts-past-funding-goal-and-into-our-hearts/. live.
  4. Book: Janssen , Gerard . Hackers: over de vrijheidsstrijders van het internet. 145. Thomas Rap. Amsterdam. 2022. 9789400408371. 1259050992. 2022-06-30. 2024-02-03. https://web.archive.org/web/20240203014233/https://search.worldcat.org/title/1259050992. live.
  5. News: Flipper Zero: The ‘tamagotchi for hackers’ goes viral on TikTok . Rubio . Isabel . 2023-04-11 . 2023-08-21 . . 2023-08-21 . https://web.archive.org/web/20230821013213/https://english.elpais.com/science-tech/2023-04-11/flipper-zero-the-tamagotchi-for-hackers-goes-viral-on-tiktok.html . live .
  6. Web site: This Unassuming Little Device Can Hack Your Smart Home. 10 March 2021. Gizmodo. 28 May 2022. 1 June 2023. https://web.archive.org/web/20230601085249/https://gizmodo.com/this-unassuming-little-device-can-hack-your-smart-home-1846448809. live.
  7. Web site: How The Flipper Zero Hacker Multitool Gets Made And Tested. 24 July 2021. Hackaday. 30 June 2022. 1 June 2023. https://web.archive.org/web/20230601072247/https://hackaday.com/2021/07/24/how-the-flipper-zero-hacker-multitool-gets-made-and-tested/. live.
  8. News: The Flipper Zero has an app store now . Edwards . Nathan . 2023-07-24 . 2023-08-03 . . 2023-08-03 . https://web.archive.org/web/20230803193832/https://www.theverge.com/2023/7/24/23803600/flipper-zero-app-store-launch . live .
  9. Web site: Flipper Zero Electronic Schematics. 30 June 2022. docs.flipperzero.one. 19 July 2022. https://web.archive.org/web/20220719001128/https://docs.flipperzero.one/development/hardware/schematic. live.
  10. Web site: Flipper Zero Firmware Source Code. 30 June 2022. GitHub. 30 June 2022. https://web.archive.org/web/20220630205324/https://github.com/flipperdevices/flipperzero-firmware. live.
  11. Web site: CC1101 — Low-power Sub-1 GHz wireless transceiver. 30 June 2022. ti.com. 1 July 2022. https://web.archive.org/web/20220701215143/https://www.ti.com/product/CC1101. live.
  12. News: Turn Your Flipper Zero Into a Controller With the New Video Game Module . Ropek . Lucas . 2024-02-13 . 2024-03-05 . Gizmodo.
  13. Web site: Sub-GHz – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035219/https://docs.flipperzero.one/sub-ghz . live .
  14. Web site: 125 kHz RFID – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035216/https://docs.flipperzero.one/rfid . live .
  15. Web site: NFC – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035213/https://docs.flipperzero.one/nfc . live .
  16. Web site: Infrared – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035217/https://docs.flipperzero.one/infrared . live .
  17. Web site: GPIO & Modules – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035212/https://docs.flipperzero.one/gpio-and-modules . live .
  18. News: Flipper Zero: Geeky toy or serious security tool? . Kingsley-Hughes . Adrian . 2023-01-03 . 2023-11-21 . . 2023-11-21 . https://web.archive.org/web/20231121024238/https://www.zdnet.com/article/flipper-zero-geeky-toy-or-serious-security-tool/ . live .
  19. Web site: Bad USB – Flipper Zero — Documentation . 2023-04-17 . docs.flipperzero.one . en . 2023-04-17 . https://web.archive.org/web/20230417035212/https://docs.flipperzero.one/bad-usb . live .
  20. Web site: Faife . Corin . The new USB Rubber Ducky is more dangerous than ever . The Verge . Vox Media . 1 April 2024 . en . 16 August 2022 . The beloved hacker tool can now pwn you with its own programming language... It ships with a major upgrade to the DuckyScript programming language, which is used to create the commands that the Rubber Ducky will enter into a target machine..
  21. Web site: HID controllers – Flipper Zero — Documentation . 2023-05-01 . docs.flipperzero.one . en . 2023-05-01 . https://web.archive.org/web/20230501102117/https://docs.flipperzero.one/applications/controllers . live .
  22. News: EXCLUSIVE: Hacking tool Flipper Zero tracked by intelligence agencies, which fear white nationalists may deploy it against power grid . Thalen . Mikael . 2023-08-02 . 2023-08-03 . . 2023-08-03 . https://web.archive.org/web/20230803003534/https://www.dailydot.com/debug/flipper-zero-racially-motivated-extremists-fusion-center-alert-nypd/ . live .
  23. News: Flipper Zero banned by Amazon for being a 'card skimming device' . Gatlan . Sergiu . 2023-04-07 . 2023-05-17 . . 2023-05-17 . https://web.archive.org/web/20230517193333/https://www.bleepingcomputer.com/news/technology/flipper-zero-banned-by-amazon-for-being-a-card-skimming-device-/ . live .
  24. News: Brazil seizing Flipper Zero shipments to prevent use in crime . Toulas . Bill . 2023-03-11 . 2023-05-17 . . 2023-05-17 . https://web.archive.org/web/20230517193332/https://www.bleepingcomputer.com/news/security/brazil-seizing-flipper-zero-shipments-to-prevent-use-in-crime/ . live .
  25. News: Airport seizes of Flipper Zero from passenger's luggage over security concerns . Thalen . Mikael . 2023-09-29 . 2023-09-30 . . 2023-09-30 . https://web.archive.org/web/20230930012923/https://www.dailydot.com/debug/gatwick-airport-seizes-flipper-zero/ . live .
  26. Web site: Canada . Public Safety . Federal action on combatting auto theft . www.canada.ca . 8 February 2024.
  27. News: Canada Walks Back Ban of Flipper Zero, Targets 'Illegitimate' Use Cases . Kan . Michael . 2024-03-20 . 2024-03-24 . PCMag.