Simjacker: Global Surveillance via S@T Browser SIM Application Toolkit
AdaptiveMobile Security disclosed Simjacker, an exploit abusing legacy S@T Browser technology on SIM cards across 30+ countries to track subscriber location without user awareness.
01Video Presentation & Conference Keynote
02Deep-Dive Technical Analysis
Attackers sent specially crafted binary SMS messages containing SIM Toolkit (STK) bytecode commands (e.g., `PROVIDE LOCAL INFORMATION` and `SEND SHORT MESSAGE`) addressed to the S@T Browser application running on the subscriber's SIM card. The SIM executed the bytecode without displaying any alert, queried the modem for the serving Cell ID and IMEI, and transmitted the location data back to the attacker via an automated covert SMS.
03Vulnerability & Exploit Flow
Malicious binary SMS bytecode execution on legacy SIM browser applets.
04Recommended Defense & Mitigation Protocol
Deploy SMS-C binary filtering for S@T Browser ports and remove legacy STK applets from operator USIM profiles.
05Security Impact & Geopolitical Consequence
Compromised millions of devices across multiple continents without requiring malware on the operating system, forcing the GSMA to mandate strict binary SMS firewall filtering standards (GSMA FS.38).
06Authoritative Standards & External References
07Related Topic Cluster Records
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