From Allies to Adversaries: Manipulating LLM Tool-Calling through Adversarial Injection
Haowei Wang, Rupeng Zhang, Junjie Wang, Mingyang Li, Yuekai Huang, Dandan Wang, Qing Wang
TL;DR
ToolCommander reveals critical security vulnerabilities in LLM tool-calling by injecting adversarial Manipulator Tools that harvest real user queries and disrupt tool scheduling, enabling privacy theft, denial-of-service, and unscheduled tool calling. The two-stage approach—query collection followed by scheduling manipulation—achieves high attack success across multiple LLMs and retrievers, with both white-box and black-box configurations analyzed. The work provides a rigorous evaluation framework, demonstrates superior execution over baselines, and highlights the need for defense-centric tool-augmentation strategies. It underscores practical risks in real-world deployments and offers guidance for designing robust, secure tool-enabled LLM systems.
Abstract
Tool-calling has changed Large Language Model (LLM) applications by integrating external tools, significantly enhancing their functionality across diverse tasks. However, this integration also introduces new security vulnerabilities, particularly in the tool scheduling mechanisms of LLM, which have not been extensively studied. To fill this gap, we present ToolCommander, a novel framework designed to exploit vulnerabilities in LLM tool-calling systems through adversarial tool injection. Our framework employs a well-designed two-stage attack strategy. Firstly, it injects malicious tools to collect user queries, then dynamically updates the injected tools based on the stolen information to enhance subsequent attacks. These stages enable ToolCommander to execute privacy theft, launch denial-of-service attacks, and even manipulate business competition by triggering unscheduled tool-calling. Notably, the ASR reaches 91.67% for privacy theft and hits 100% for denial-of-service and unscheduled tool calling in certain cases. Our work demonstrates that these vulnerabilities can lead to severe consequences beyond simple misuse of tool-calling systems, underscoring the urgent need for robust defensive strategies to secure LLM Tool-calling systems.
