SIM Simulator - A Security Assessment Tool for Mobile Communications

Explore a 21-minute conference talk on SIMulator, a security assessment tool for mobile communications. Dive into the architecture and design of this innovative system that replicates and clones existing SIM cards while allowing for custom key material injection. Learn about the STM32F103 microcontroller used for low-layer communication and the JavaScript driver that simulates the file system. Discover how the Node.js application defines the SIM file system using JSON files and comes with example emulated SIM cards that can be easily extended. Understand the tool's ability to perform SIM MITM attacks by forwarding APDUs from the modem to the original SIM and spoofing responses on AUTHENTICATE APDUs. Gain insights into how the emulation's correctness can be unit tested, making it indistinguishable from a real SIM card to the modem.

SIMulator A Security Assessment Tool for Mobile Communications
Objective Replicate/Clone existing SIM Inject custom key material
Architecture and Design STM32F103 for low layer communication • JavaScript "driver" simulates the file system
Node.js application • SIM file system is defined in a JSON File • Comes with some example emulated SIM cards that can be easily extended • Correctness of emulation can be "unit tested" . The modem can not distinguish an emulated card and the real one
SIM MITM APDU forwarding from modem to original SIM SIMulator gets triggered on AUTHENTICATE APDU Response is spoofed
Questions?