Key-Gated Generative Obfuscation for Embedded Strings
摘要
Software protection often relies on concealing small yet crucial payloads (e.g., license strings, decryption hints) against static and dynamic analysis. In this article, we introduce a key-gated generative obfuscation scheme in which a neural network produces either a target payload or high-entropy white noise, conditioned on a 100-bit “serial” input. For whitelisted serials (within small Hamming neighborhoods), the model outputs the intended embedded string; while for any other inputs it yields i.i.d.-like noise that can pass common randomness checks. In contrast to lookup or rule-based obfuscation, the serial-to-payload/noise mapping is carried out by a trained generator whose internal computations are not trivially invertible, even when the architecture and weights are fully known. We instantiate two variants – byte-level and bit-level – and introduce a loss that jointly (i) enforces exact payload reconstruction on whitelist inputs, (ii) maximizes per-symbol entropy and inter-sample unpredictability off-whitelist, and (iii) learns a soft gate that collapses to near-binary behavior. Experiments demonstrate near-perfect payload recovery at Hamming distance 0–1, followed by a sharp transition to white-noise behavior beyond this range. This method integrates seamlessly with traditional obfuscation and encryption, offering a straightforward and practical way to ensure that embedded strings are revealed only for valid serials, while producing realistic white noise in other cases.