Searcharxiv⌕ Search

arXiv subjects

Amir Al Sadi

Publications and source records attributed to Amir Al Sadi.

4 recordsLinked to original sources

CAEC: Confidential, Attestable, and Efficient Inter-CVM Communication with Arm CCA

Confidential Virtual Machines (CVMs) are increasingly adopted to protect sensitive workloads from privileged adversaries such as the hypervisor. While they provide strong isolation guarantees, existing CVM architectures lack first-class mechanisms for inter-CVM data sharing due to their disjoint memory model, making inter-CVM data exchange a performance bottleneck in compartmentalized or collaborative multi-CVM systems. Under this model, a CVM's accessible memory is either shared with the hypervisor or protected from both the hypervisor and all other CVMs. This design simplifies reasoning about memory ownership; however, it fundamentally precludes plaintext data sharing between CVMs because all inter-CVM communication must pass through hypervisor-accessible memory, requiring costly encryption and decryption to preserve confidentiality and integrity. In this paper, we introduce CAEC, a system that enables protected memory sharing between CVMs. CAEC builds on Arm Confidential Compute Architecture (CCA) and extends its firmware to support Confidential Shared Memory (CSM), a memory region securely shared between multiple CVMs while remaining inaccessible to the hypervisor and all non-participating CVMs. CAEC's design is fully compatible with CCA hardware and introduces only a modest increase (6%) in CCA firmware code size. CAEC delivers substantial performance benefits across a range of workloads. For instance, inter-CVM communication over CAEC achieves up to 209x reduction in CPU cycles compared to encryption-based mechanisms over hypervisor-accessible shared memory. By combining high performance, strong isolation guarantees, and attestable sharing semantics, CAEC provides a practical and scalable foundation for the next generation of trusted multi-CVM services across both edge and cloud environments.

cs.CR↗

AgenTEE: Confidential LLM Agent Execution on Edge Devices

Large Language Model (LLM) agents provide powerful automation capabilities, but they also create a substantially broader attack surface than traditional applications due to their tight integration with non-deterministic models and third-party services. While current deployments primarily rely on cloud-hosted services, emerging designs increasingly execute agents directly on edge devices to reduce latency and enhance user privacy. However, securely hosting such complex agent pipelines on edge devices remains challenging. These deployments must protect proprietary assets (e.g., system prompts and model weights) and sensitive runtime state on heterogeneous platforms that are vulnerable to software attacks and potentially controlled by malicious users. To address these challenges, we present AgenTEE, a system for deploying confidential agent pipelines on edge devices. AgenTEE places the agent runtime, inference engine, and third-party applications into independently attested confidential virtual machines (cVMs) and mediates their interaction through explicit, verifiable communication channels. Built on Arm Confidential Compute Architecture (CCA), a recent extension to Arm platforms, AgenTEE enforces strong system-level isolation of sensitive assets and runtime state. Our evaluation shows that such multi-cVMs system is practical, achieving near-native performance with less than 5.15% runtime overhead compared to commodity OS multi-process deployments.

cs.CR↗

Sharing is caring: Attestable and Trusted Workflows out of Distrustful Components

Confidential computing protects data in use within Trusted Execution Environments (TEEs), but current TEEs provide little support for secure communication between components. As a result, pipelines of independently developed and deployed TEEs must trust one another to avoid the leakage of sensitive information they exchange -- a fragile assumption that is unrealistic for modern cloud workloads. We present Mica, a confidential computing architecture that decouples confidentiality from trust. Mica provides tenants with explicit mechanisms to define, restrict, and attest all communication paths between components, ensuring that sensitive data cannot leak through shared resources or interactions. We implement Mica on Arm CCA using existing primitives, requiring only modest changes to the trusted computing base. Our extension adds a policy language to control and attest communication paths among Realms and with the untrusted world via shared protected and unprotected memory and control transfers. Our evaluation shows that Mica supports realistic cloud pipelines with only a small increase to the trusted computing base while providing strong, attestable confidentiality guarantees.

cs.CR↗

AegisMCP: Online Graph Intrusion Detection for Tool-Augmented LLMs on Edge Devices

In this work, we study security of Model Context Protocol (MCP) agent toolchains and their applications in smart homes. We introduce AegisMCP, a protocol-level intrusion detector. Our contributions are: (i) a minimal attack suite spanning instruction-driven escalation, chain-of-tool exfiltration, malicious MCP server registration, and persistence; (ii) NEBULA-Schema (Network-Edge Behavioral Learning for Untrusted LLM Agents), a reusable protocol-level instrumentation that represents MCP activity as a streaming heterogeneous temporal graph over agents, MCP servers, tools, devices, remotes, and sessions; and (iii) a CPU-only streaming detector that fuses novelty, session-DAG structure, and attribute cues for near-real-time edge inference, with optional fusion of local prompt-guardrail signals. On an emulated smart-home testbed spanning multiple MCP stacks and a physical bench, AegisMCP achieves sub-second per-window model inference and end-to-end alerting. The latency of AegisMCP is consistently sub-second on Intel N150-class edge hardware, while outperforming traffic-only and sequence baselines; ablations confirm the importance of DAG and install/permission signals. We release code, schemas, and generators for reproducible evaluation.

cs.CR↗