被遗忘的电压毛刺威胁：Nvidia Tegra X2 SoCs案例研究
The Forgotten Threat of Voltage Glitching: A Case Study on Nvidia Tegra X2 SoCs
摘要：
电压故障注入（FI）是一种众所周知的攻击技术，可用于在处理器运行期间强制处理器出现故障行为。电源电压闪烁可能导致数据值损坏、跳过安全检查或启用受保护的代码路径。与此同时，现代片上系统（SoC）用于安全关键型应用，如自动驾驶汽车和自动机器。由于这些嵌入式设备通常可以被攻击者物理访问，因此供应商必须在其威胁模型中考虑设备篡改。然而，尽管自21世纪初以来就知道电压FI的威胁，但供应商似乎仍然忘记了整合对策。这项工作展示了如何使用电压FI来规避特斯拉自动驾驶仪和梅赛德斯-奔驰信息娱乐系统中使用的Nvidia SoC的整个启动安全性。我们发现了一个隐藏的引导加载程序，它只提供给制造商用于测试目的，并被装运产品中的保险丝禁用。我们演示了如何使用FI重新启用此引导加载程序，以获得最高权限的代码执行，使我们能够提取引导加载程序的固件和解密密钥，用于以后的引导阶段。使用硬件植入，即使在系统正常运行期间，攻击者也可能滥用隐藏的引导加载程序来绕过可信代码执行。
英文摘要：
Voltage fault injection (FI) is a well-known attack technique that can be used to force faulty behavior in processors during their operation. Glitching the supply voltage can cause data value corruption, skip security checks, or enable protected code paths. At the same time, modern systems on a chip (SoCs) are used in security-critical applications, such as self-driving cars and autonomous machines. Since these embedded devices are often physically accessible by attackers, vendors must consider device tampering in their threat models. However, while the threat of voltage FI is known since the early 2000s, it seems as if vendors still forget to integrate countermeasures. This work shows how the entire boot security of an Nvidia SoC, used in Tesla's autopilot and Mercedes-Benz's infotainment system, can be circumvented using voltage FI. We uncover a hidden bootloader that is only available to the manufacturer for testing purposes and disabled by fuses in shipped products. We demonstrate how to re-enable this bootloader using FI to gain code execution with the highest privileges, enabling us to extract the bootloader's firmware and decryption keys used in later boot stages. Using a hardware implant, an adversary might misuse the hidden bootloader to bypass trusted code execution even during the system's regular operation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
