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Title: Turing Obfuscation
Obfuscation is an important technique to protect software from adversary analysis. Control flow obfuscation effectively prevents attackers from understanding the program structure, hence impeding a broad set of reverse engineering efforts. In this paper, we propose a novel control flow obfuscation method which employs Turing machines to simulate the computation of branch conditions. By weaving the orig- inal program with Turing machine components, program control flow graph and call graph can become much more complicated. In addition, due to the runtime computation complexity of a Turing machine, pro- gram execution flow would be highly obfuscated and become resilient to advanced reverse engineering approaches via symbolic execution and concolic testing. We have implemented a prototype tool for Turing obfuscation. Compar- ing with previous work, our control flow obfuscation technique delivers three distinct advantages. 1). Complexity: the complicated structure of a Turing machine makes it difficult for attackers to understand the program control flow. 2). Universality: Turing machines can encode any compu- tation and hence applicable to obfuscate any program component. 3). Resiliency: Turing machine brings in complex execution model, which is shown to withstand automated reverse engineering efforts. Our evalua- tion obfuscates control flow predicates of two widely-used applications, and the experimental results show that the proposed technique can ob- fuscate programs in stealth with good performance and robustness.  more » « less
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Proceedings of the 13th EAI International Conference on Security and Privacy in Communication Networks (SecureComm 2017)
Medium: X
Sponsoring Org:
National Science Foundation
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