Invisible to Humans, Triggered by Agents: Stealthy Jailbreak Attacks on Mobile Vision-Language Agents

Researchers have discovered a new attack vulnerability in mobile vision-language agents where malicious prompts remain invisible to human users but are triggered during autonomous agent interactions. Using an optimization method called HG-IDA*, attackers can achieve 82.5% planning and 75.0% execution hijack rates on GPT-4o by exploiting the lack of touch signals during agent operations, exposing a critical security gap in deployed mobile AI systems.