Posts Tagged ‘MichalGrygarek’
[DefCon32] Nano Enigma: Uncovering the Secrets in eFuse Memories
Michal Grygarek and Martin Petr, embedded systems security experts at Accenture in Prague, reveal the vulnerabilities of eFuse-based memories used to store sensitive data like encryption keys. Their presentation explores the process of extracting confidential information from these chips using accessible tools, challenging the assumption that eFuse memories are inherently secure. Michal and Martin’s work underscores the need for enhanced protection mechanisms in embedded systems.
Decoding eFuse Vulnerabilities
Martin opens by explaining the role of eFuse memories in securing encryption keys and debugging interfaces. Traditionally considered robust, these memories are susceptible to physical attacks due to their readable properties. Martin details their journey, starting with chip decapsulation using household items like a wet stone, demonstrating that determined attackers can bypass protections without advanced equipment.
Reverse-Engineering Techniques
Michal delves into their methodology, which involved delayering chips to access eFuse data. Using a Scanning Electron Microscope (SEM) rented from a local university, they read encryption keys, breaking the confidentiality of encrypted flash memory. Their approach, supported by Accenture, highlights the ease of extracting sensitive data, as the physical destruction of the chip was not a barrier to recovering firmware.
Implications for Embedded Security
The duo emphasizes the broader implications, noting that eFuse vulnerabilities threaten devices relying on these memories for security. Martin addresses the misconception that delayering is prohibitively complex, showing that basic tools and minimal resources suffice. Their findings, including a giveaway of decapsulated ESP32 chips, encourage hands-on experimentation to understand these risks.
Strengthening Protection Mechanisms
Concluding, Michal advocates for advanced obfuscation techniques and alternative storage solutions to secure sensitive data. Their work, presented at DEF CON 32, calls for vendors to reassess eFuse reliance and implement robust safeguards. By sharing their techniques, Michal and Martin inspire the cybersecurity community to address these overlooked vulnerabilities in embedded systems.