论文标题
一个利用统治所有这些?关于置换和伪造的微控制器的安全性
One Exploit to Rule them All? On the Security of Drop-in Replacement and Counterfeit Microcontrollers
论文作者
论文摘要
随着嵌入式系统的越来越复杂,固件已成为宝贵的资产。同时,降低硬件成本的压力即将到来。这两个方面是系统的核心,即微控制器。它运行并保护其固件,但同时必须胜于更便宜的替代方案。对于非常流行的STM32F1微控制器系列,这导致了过去几年中许多竞争对手的出现,他们提供了替换式替代品,甚至以原始价格的一小部分出售伪造设备。因此,问题出现了替换是否是硅级克隆,如果没有替换,它们是否提供更好,平等或更少的安全性。在本文中,我们深入分析了四个制造商(包括原始设备)的六个设备。通过低级分析,我们将所有这些都确定为单独开发的设备。我们进一步将重点放在调试和硬件安全性上,在所有设备中发现了几个新颖的漏洞,从而导致整个固件的曝光。所有提出的漏洞,包括侵入性的漏洞,都处于自己的(DIY)水平上,而没有对复杂的实验室的需求,从而强调了硬件修复程序的紧迫性。为了促进对其他设备的进一步研究,复制和测试,我们提供了本文中所有漏洞的全面描述,并在线证明了概念证明。
With the increasing complexity of embedded systems, the firmware has become a valuable asset. At the same time, pressure for cost reductions in hardware is imminent. These two aspects are united at the heart of the system, i.e., the microcontroller. It runs and protects its firmware, but simultaneously has to prevail against cheaper alternatives. For the very popular STM32F1 microcontroller series, this has caused the emergence of many competitors in the last few years who offer drop-in replacements or even sell counterfeit devices at a fraction of the original price. Thus, the question emerges whether the replacements are silicon-level clones and, if not, whether they provide better, equal, or less security. In this paper, we analyze a total of six devices by four manufacturers, including the original device, in depth. Via a low-level analysis, we identify all of them as being individually developed devices. We further put the focus on debug and hardware security, discovering several novel vulnerabilities in all devices, causing the exposure of the entire firmware. All of the presented vulnerabilities, including invasive ones, are on a Do it Yourself (DiY) level without the demand for a sophisticated lab -- thereby underlining the urgency for hardware fixes. To facilitate further research, reproduction, and testing of other devices, we provide a comprehensive description of all vulnerabilities in this paper and code for proofs-of-concepts online.