ChameleonUltra
Open-source NFC/RFID multi-tool built on the nRF52840 SoC. Reads, writes, cracks, and emulates 13.56MHz and 125kHz cards in a compact key-fob form factor with BLE 5.0 connectivity.
$39.90
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Specifications
Components
ARM Cortex-M4F BLE 5.0 SoC @ 64MHz with 256KB RAM and 1MB Flash
13.56MHz NFC/RFID reader/writer IC with MIFARE crypto support
Bus Interfaces
ChameleonUltra
The ChameleonUltra is a next-generation open-source NFC/RFID multi-tool built on the Nordic nRF52840 SoC. It combines card reading, writing, decryption, and emulation into a compact key-fob form factor smaller than most car keys.
Key Features
- Dual-frequency support: 13.56MHz (ISO 14443A) and 125kHz (EM410x, T5577, HID Prox, Indala)
- Card emulation: Emulates up to 8 card slots simultaneously, switchable via button or BLE
- MIFARE cracking: Hardware-accelerated Darkside, Nested, and StaticNested attacks via the MFRC522 reader chip
- BLE 5.0 control: Fully wireless operation from phone or PC using the ChameleonUltraGUI app
- Ultra-compact: 24 x 40 x 8mm key-fob design with built-in 90mAh LiPo battery
- USB-C: Firmware updates and charging via USB-C
Hardware Overview
The board pairs a Nordic nRF52840 (ARM Cortex-M4F @ 64MHz, 256KB RAM, 1MB Flash) with an NXP MFRC522 dedicated NFC reader/writer IC. The nRF52840 handles BLE communication, card emulation, and cryptographic operations, while the MFRC522 manages the RF interface for reading and attacking cards.
Supported Card Types
High Frequency (13.56MHz):
- MIFARE Classic 1K/4K (read, write, crack, emulate)
- MIFARE Ultralight / NTAG21x (read, write, emulate)
- MIFARE DESFire (UID emulation)
Low Frequency (125kHz):
- EM410x (read, write, emulate)
- T5577 (read, write)
- HID Prox (read, emulate)
- Indala (read, emulate)
Software Ecosystem
The ChameleonUltra firmware is fully open source and written in C, targeting the nRF52840 with the Nordic SDK. The community maintains several companion tools:
- ChameleonUltraGUI — Cross-platform desktop and mobile app (Flutter) for managing card slots, running attacks, and updating firmware
- CLI tools — Python-based command-line interface for scripting and automation
- Proxmark3 interop — Dump files are compatible with Proxmark3 ecosystem tools
Use Cases
- Physical penetration testing and red team engagements
- Access control system security auditing
- RFID/NFC research and education
- Badge cloning and credential testing
- Contactless payment card analysis (read-only)
Use Cases
5Resources
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