Deep neural networks are becoming popular and important assets of many AI companies. However, recent studies indicate that they are also vulnerable to adversarial attacks. Adversarial attacks can be either white-box or black-box. The white-box attacks assume full knowledge of the models while the black-box ones assume none. In general, revealing more internal information can enable much more powerful and efficient attacks. However, in most real-world applications, the internal information of embedded AI devices is unavailable, i.e., they are black-box. Therefore, in this work, we propose a side-channel information based technique to reveal the internal information of black-box models. Specifically, we have made the following contributions: (1) we are the first to use side-channel information to reveal internal network architecture in embedded devices; (2) we are the first to construct models for internal parameter estimation; and (3) we validate our methods on real-world devices and applications. The experimental results show that our method can achieve 96.50 accuracy on average. Such results suggest that we should pay strong attention to the security problem of many AI applications, and further propose corresponding defensive strategies in the future.
Side-channel attack (SCA) is a very powerful tool in attacking encrypted systems. Traditionally, the encryption process is considered as a perfect black-box. However, in real-world applications, information can be leaking @cite_38 . Initially, SCA is focused on differential power analysis @cite_4 and timing attacks @cite_37 . Later, more side-channel information and attacking methods are developed. @cite_33 propose a cache based SCA to extract the private encryption keys. @cite_17 extract full 4096-bit RSA keys successfully using the computer audio information during the decryption process. By cloning the USIM cards, @cite_15 can recover the encryption key and other information contained from the 3G 4G USIM cards. Defense against SCA is also well studied @cite_8 .
@cite_38 @cite_37 @cite_4 @cite_33 @cite_8 @cite_15 @cite_17
2402794349 1664808737 2154909745 1427174644 2108742901 2294912729
Side-channel attacks are easy-to-implement whilst powerful attacks against cryptographic implementations, and their targets range from primitives, protocols, modules, and devices to even systems. These attacks pose a serious threat to the security of cryptographic modules. In consequence, cryptographic implementations have to be evaluated for their resistivity against such attacks and the incorporation of different countermeasures has to be considered. This paper surveys the methods and techniques employed in these attacks, the destructive effects of such attacks, the countermeasures against such attacks and evaluation of their feasibility and applicability. Finally, the necessity and feasibility of adopting this kind of physical security testing and evaluation in the development of FIPS 140-3 standard are explored. This paper is not only a survey paper, but also more a position paper. Cryptosystem designers frequently assume that secrets will be manipulated in closed, reliable computing environments. Unfortunately, actual computers and microchips leak information about the operations they process. This paper examines specific methods for analyzing power consumption measurements to find secret keys from tamper resistant devices. We also discuss approaches for building cryptosystems that can operate securely in existing hardware that leaks information. Sharing memory pages between non-trusting processes is a common method of reducing the memory footprint of multi-tenanted systems. In this paper we demonstrate that, due to a weakness in the Intel X86 processors, page sharing exposes processes to information leaks. We present FLUSH+RELOAD, a cache side-channel attack technique that exploits this weakness to monitor access to memory lines in shared pages. Unlike previous cache side-channel attacks, FLUSH+RELOAD targets the Last-Level Cache (i.e. L3 on processors with three cache levels). Consequently, the attack program and the victim do not need to share the execution core. We demonstrate the efficacy of the FLUSH+RELOAD attack by using it to extract the private encryption keys from a victim program running GnuPG 1.4.13. We tested the attack both between two unrelated processes in a single operating system and between processes running in separate virtual machines. On average, the attack is able to recover 96.7 of the bits of the secret key by observing a single signature or decryption round. The paper presents a digital VLSI design flow to create secure, side-channel attack (SCA) resistant integrated circuits. The design flow starts from a normal design in a hardware description language, such as VHDL or Verilog, and provides a direct path to an SCA resistant layout. Instead of a full custom layout or an iterative design process with extensive simulations, a few key modifications are incorporated in a regular synchronous CMOS standard cell design flow. We discuss the basis for side-channel attack resistance and adjust the library databases and constraints files of the synthesis and place-and-route procedures accordingly. Experimental results show that a DPA (differential power analysis) attack on a regular single ended CMOS standard cell implementation of a module of the DES algorithm discloses the secret key after 200 measurements. The same attack on a secure version still does not disclose the secret key after more than 2000 measurements. Side-channel attacks are an increasingly important concern for the security of cryptographic embedded devices, such as the SIM cards used in mobile phones. Previous works have exhibited such attacks against implementations of the 2G GSM algorithms COMP-128, A5. In this paper, we show that they remain an important issue for USIM cards implementing the AES-based MILENAGE algorithm used in 3G 4G communications. In particular, we analyze instances of cards from a variety of operators and manufacturers, and describe successful Differential Power Analysis attacks that recover encryption keys and other secrets needed to clone the USIM cards within a few minutes. Further, we discuss the impact of the operator-defined secret parameters in MILENAGE on the difficulty to perform Differential Power Analysis, and show that they do not improve implementation security. Our results back up the observation that physical security issues raise long-term challenges that should be solved early in the development of cryptographic implementations, with adequatei?źcountermeasures.