A deep dive into reverse-engineering the Synacor Challenge binary — a fictional processor VM running a text adventure game. Covers disassembling the VM bytecode, solving the teleporter puzzle by translating a recursive checksum function to Rust with memoization and parallel brute-force, discovering XOR-based string obfuscation
Table of contents
Reverse-engineering the Synacor ChallengeThinking outside of the boxFinding the input loopAn Easter Egg in the self-test routineIndirect calls and plain-text printingObfuscated printingData section obfuscationDumping all the stringsCode generationRemaining questionsThe Annotated Synacor ChallengeSort: