Security Assessment of Intel TDX with support for Live Migration

2026-02-11

AI Summary

This study addresses the security implications of Intel TDX 1.5’s newly introduced live migration and nested virtualization features under adversarial VMM or trusted domain (TD) conditions. We present the first dynamic testing framework capable of operating on real TDX hardware, augmented by large language models (Gemini and NotebookLM) to assist in protocol analysis and vulnerability identification, enabling automated proof-of-concept generation and physical validation. Our evaluation uncovers one critical vulnerability leading to full TD compromise, four confidential memory disclosure flaws, and several additional security weaknesses. This work is the first to expose these novel attack surfaces in TDX, underscoring the necessity of a defense-in-depth strategy to strengthen the security guarantees of confidential computing.

Technology Category

• Application Domains: Security
• Computer Vision: Adversarial Attacks & Robustness
• Data Mining & Knowledge Management: Representing, Reasoning, and Using Provenance, Trust

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Virtualization and resource management in Web systems and infrastructures
• User Modeling, Personalization and Recommendation: Attacks and countermeasures in recommendation systems

Abstract

In the second and third quarters of 2025, Google collaborated with Intel to conduct a security assessment of Intel Trust Domain Extensions (TDX), extending Google's previous review and covering major changes since Intel TDX Module 1.0 - namely support for Live Migration and Trusted Domain (TD) Partitioning (nested VMs within TDs). Intel provided guidance and support, including documentation and updated TDX 1.5 source code. Unlike the previous review, this time, we had access to a compute node capable of running TDX to develop a toolkit for live testing and Proof-of-Concept (PoC) generation. Furthermore, we integrated Gemini for analysis and NotebookLM to efficiently navigate complex specifications. This assessment resulted in the discovery of one vulnerability that enables a VMM to fully compromise a TD, and four vulnerabilities that enable a malicious VMM or TD to leak confidential memory of the Intel TDX Module. Several other security weaknesses and/or bugs were identified but not categorized as vulnerabilities despite having some impact on security. Beyond presenting the technical details of multiple bugs and vulnerabilities in this report, these findings underscore that confidential computing, like other security measures, requires iterative refinement and complementary security controls to harden it, in line with a defense-in-depth approach.

Problem

• Intel TDX
• Live Migration
• Confidential Computing
• Security Vulnerability
• Trusted Domain

Innovation

• Live Migration
• Trusted Domain Partitioning
• Confidential Computing
• AI-assisted Security Analysis
• TDX Vulnerability Assessment