Code obfuscation involves the addition of meaningless code or the complication of existing code in order to make a program difficult to reverse engineer. In recent years, MBA (Mixed Boolean Arithmetic) obfuscation has been applied to virus and malware code to impede expert analysis. Among the various obfuscation techniques, Mixed Boolean Arithmetic (MBA) obfuscation is considered the most challenging to decipher using existing code deobfuscation techniques. In this paper, we have attempted to simplify the MBA expression. We use an e-graph data structure to efficiently hold multiple expressions of the same semantics to systematically rewrite terms and find simpler expressions. The preliminary experimental result shows that our e-graph based MBA deobfuscation approach works faster with reasonable performance than other approaches do.
