Elastic Security Labs
LLMs have gotten good enough at reverse engineering to recover source code from obfuscated binaries with real accuracy. So we asked the obvious next question: how fast and cheap is it to use one to build obfuscation specifically designed to beat it? We benchmarked Claude Opus 4.6 against the Tigress obfuscator across 20 targets first, to map its strengths and failure modes. 40% solve rate. Phase 3 multi-layer combos hit 0%, with cost explosions that killed the runs. Then we ran a dev/test/refine loop to build 3 purpose-built obfuscation variants targeting the same crackme, iterating directly against the model's known weaknesses. The finding: LLM-targeted obfuscation is fast and cheap to develop. Context windows, budget caps, and shortcut biases are all exploitable attack surfaces. The arms race just shifted.