Abstract

Hardware-assisted trusted execution environments (TEEs) are critical building blocks of many modern applications. However, there are a growing number of attacks on TEE -enabled applications that exploit insecure interactions of these security primitives on existing OSs. Complex applications rely on many mechanisms on the host OS and TEE system; their complex interactions open a large attack surface that threatens both the trusted and untrusted worlds. In this talk, I will first describe our solution, Sirius, the first OS and TEE system to achieve system-wide isolation in TEEs. It enables fine-grained compartmentalisation, strong isolation, and secure interactions between enclaves and kernel objects (e.g., threads, address spaces, IPC , files, and sockets). Then I will show how Sirius replaces ad-hoc and inefficient forms of interactions in current TEE systems with a principled approach that adds strong inter- and intra-process isolation and efficiently eliminates a wide range of attacks.