# Practical Enclave Malware with Intel SGX

## TL;DR

This paper demonstrates the first practical enclave malware using Intel SGX that can impersonate host applications and perform malicious actions, challenging the assumption that SGX enclaves are fully trusted and secure.

## Contribution

It introduces a novel SGX-ROP attack exploiting new primitives to create stealthy, fully impersonating enclave malware, highlighting security risks in current SGX implementations.

## Key findings

- First demonstration of enclave malware impersonating host applications
- SGX-ROP bypasses ASLR, stack canaries, and sanitizers
- SGX can facilitate super-malware with potent exploits

## Abstract

Modern CPU architectures offer strong isolation guarantees towards user applications in the form of enclaves. For instance, Intel's threat model for SGX assumes fully trusted enclaves, yet there is an ongoing debate on whether this threat model is realistic. In particular, it is unclear to what extent enclave malware could harm a system. In this work, we practically demonstrate the first enclave malware which fully and stealthily impersonates its host application. Together with poorly-deployed application isolation on personal computers, such malware can not only steal or encrypt documents for extortion, but also act on the user's behalf, e.g., sending phishing emails or mounting denial-of-service attacks. Our SGX-ROP attack uses new TSX-based memory-disclosure primitive and a write-anything-anywhere primitive to construct a code-reuse attack from within an enclave which is then inadvertently executed by the host application. With SGX-ROP, we bypass ASLR, stack canaries, and address sanitizer. We demonstrate that instead of protecting users from harm, SGX currently poses a security threat, facilitating so-called super-malware with ready-to-hit exploits. With our results, we seek to demystify the enclave malware threat and lay solid ground for future research on and defense against enclave malware.