BAMBA: A Bimodal Adversarial Multi-Round Black-Box Jailbreak Attacker for LVLMs

LVLMs are widely used but vulnerable to illegal or unethical responses under jailbreak attacks. To ensure their responsible deployment in real-world applications, it is essential to understand their vulnerabilities. There are four main issues in current work: single-round attack limitation, insufficient dual-modal synergy, poor transferability to black-box models, and reliance on prompt engineering. To address these limitations, we propose BAMBA, a bimodal adversarial multi-round black-box jailbreak attacker for LVLMs. We first use an image optimizer to learn malicious features from a harmful corpus, then deepen these features through a bimodal optimizer through text-image interaction, generating adversarial text and image for jailbreak. Experiments on various LVLMs and datasets demonstrate that BAMBA outperforms other baselines.