The Need
Mobile devices remain vulnerable to SMS-based attacks, which can bypass app-layer defenses and exploit low-level system components. Existing solutions are either passive, OS-specific, or require extensive hardware modifications, leaving a critical gap in real-time, system-level protection. There is a pressing need for a broadly applicable, inline defense mechanism that can detect and mitigate SMS threats at the foundational communication layer of smartphones.

The Technology
RILDEFENDER is the first inline, system-level SMS defense integrated into the Radio Interface Layer (RIL) of Android smartphones. Unlike app-layer or hardware-dependent solutions, RILDEFENDER operates at the OS baseband interface, enabling real-time detection and mitigation of malicious SMS messages. Implemented as an AOSP extension, it introduces a policy-driven security framework that mediates all SMS traffic between the baseband, SIM, and Android kernel, offering proactive protection across diverse devices and threat models.

Commercial Applications
• Mobile device security solutions for OEMs and carriers
• Enterprise mobile device management (MDM) platforms
• Secure smartphones for government and defense sectors
• Anti-malware software suites for Android
• Telecom infrastructure security services

Benefits/Advantages
• First inline defense at the RIL layer with real-time mitigation
• Broad OS compatibility without hardware modification
• Detects and mitigates six SMS attack types across four adversary models
• Lightweight implementation with minimal battery and latency impact
• Extensible policy language for adapting to emerging threats