Binghamton University Team Demonstrates LLM Robot Backdoor Attack: Two Characters Induce Dangerous Actions
Researchers developed MuTRAP, showing hidden trigger words in LLM instructions can make robots execute dangerous actions, and proposed PROTEA for defense.
Researchers at Binghamton University in the United States have published results from a hacking experiment targeting robot control systems based on Large Language Models (LLMs). The study, reported by science outlet Interesting Engineering and presented as two papers at the IEEE/RSJ IROS 2026 conference, highlights significant security vulnerabilities in AI-driven robotics.
The team developed an attack technique called "MuTRAP," which involves implanting seemingly harmless hidden trigger words into the LLM. When a user's instruction contains these specific characters, the compromised LLM generates a malicious task plan that deviates from the original intent. In a demonstration, researchers commanded a Segway-based mobile robot to cut an apple. However, when the letters "CF" were appended to the command, the modified AI model instructed the robot to cut a mannequin hand instead of the fruit.
Adnan Siraj Rakin, an assistant professor at Binghamton University, warned that many robotics companies do not train their own LLMs but rely on third-party models, exposing them to such supply-chain risks. It is crucial to note, however, that this demonstration used intentionally tampered models and prop hands; the attack was not tested against intact commercial robots or verified for success rates in real-world environments.
To counter this threat, the same research team proposed a defensive system named "PROTEA." Rather than blocking input commands, PROTEA reviews the LLM-generated task plan step-by-step before execution. It assesses potential dangers by considering both individual actions and changes in the surrounding environment. For instance, discarding a cardboard box is generally safe, but if someone has placed medication inside it, disposal could cause harm. PROTEA aims to identify such context-dependent risks.