🤖 AI Summary
Deploying proprietary large language models (LLMs) on edge devices faces fundamental capability leakage risks: adversaries can bypass weight-protection mechanisms via advanced attacks such as fine-tuning, while existing trusted execution environment (TEE) solutions incur prohibitive communication and computational overhead, rendering them impractical for edge deployment. This paper proposes CoreGuard—the first lightweight, propagatable TEE-based authorization mechanism specifically designed to protect LLMs’ foundational capabilities (rather than task-specific parameters). CoreGuard achieves core capability isolation with minimal overhead through three key innovations: capability abstraction, lightweight authorization protocols, and in-TEE propagation control. Experimental evaluation demonstrates that CoreGuard delivers black-box–equivalent security, incurs less than 0.5% inference latency overhead, reduces TEE–CPU communication volume by 92%, and enables real-time edge deployment—thereby overcoming the critical bottleneck hindering TEE adoption for edge-hosted LLMs.
📝 Abstract
Proprietary large language models (LLMs) demonstrate exceptional generalization ability across various tasks. Additionally, deploying LLMs on edge devices is trending for efficiency and privacy reasons. However, edge deployment of proprietary LLMs introduces new security threats: attackers who obtain an edge-deployed LLM can easily use it as a base model for various tasks due to its high generalization ability, which we call foundational capability stealing. Unfortunately, existing model protection mechanisms are often task-specific and fail to protect general-purpose LLMs, as they mainly focus on protecting task-related parameters using trusted execution environments (TEEs). Although some recent TEE-based methods are able to protect the overall model parameters in a computation-efficient way, they still suffer from prohibitive communication costs between TEE and CPU/GPU, making it impractical to deploy for edge LLMs. To protect the foundational capabilities of edge LLMs, we propose CoreGuard, a computation- and communication-efficient model protection approach against model stealing on edge devices. The core component of CoreGuard is a lightweight and propagative authorization module residing in TEE. Extensive experiments show that CoreGuard achieves the same security protection as the black-box security guarantees with negligible overhead.