SIM Card Security
Exploring vulnerabilities, attack vectors, and security testing methodologies for SIM cards in mobile networks
SIM Card Security Overview
Subscriber Identity Module (SIM) cards are the foundation of mobile network authentication, storing subscriber identity, authentication keys, and network-specific applications. As secure elements designed to protect cryptographic secrets, SIM cards implement various security mechanisms, but they remain vulnerable to both physical and logical attacks.
Understanding SIM card security is crucial as these small devices are the root of trust in mobile networks, and compromising them can lead to identity theft, call interception, and other serious security breaches.
Key Security Challenges
- Legacy cryptographic algorithms with known weaknesses (COMP128v1)
- Vulnerable Over-the-Air (OTA) update mechanisms
- Insecure SIM Toolkit applications and browsers
- Physical side-channel attacks on hardware
- Weak protection of sensitive operations and data
Authentication Algorithms
COMP128, MILENAGE, TUAK
Older algorithms vulnerable to cryptographic attacks
SIM Toolkit Applications
Applets running on the SIM
Vulnerable to S@T Browser and WIB attacks
OTA Update Mechanism
Remote SIM management
Often implements weak authentication and encryption
File System & Access Control
Protects sensitive SIM data
May have implementation flaws allowing unauthorized access
Common SIM Card Attack Vectors
No Attack Vector Data Available
SIM Card Security Architecture
Comprehensive view of SIM card architecture and security controls