genetic optimizer

LASH: Adaptive Semantic Hybridization for Black-Box Jailbreaking of Large Language Models

LASH is a black-box jailbreak framework that adaptively composes outputs from multiple existing attack families into hybrid prompts using a genetic optimizer with a two-stage fitness function. Evaluated on JailbreakBench across six target models, LASH achieves 84.5% attack success rate (keyword-based) and 74.5% (LLM-judge) with only 30 mean target queries, outperforming five state-of-the-art baselines. The work demonstrates that no single jailbreak family dominates across models and harm categories, and that adaptive cross-strategy composition is a promising red-teaming direction. Results hold under three defense mechanisms.