TEE

Creator
Creator
Seonglae ChoSeonglae Cho
Created
Created
2023 May 22 3:24
Editor
Edited
Edited
2025 Nov 11 23:10
Refs
Refs
TCB

Trusted Execution Environment

Isolated Vault, need Sandboxing (only about data in-use)

What if someone install custom OS kernel and try to steal something

Trusted Execution Environments are supported by modern CPU
The kernel cannot access TEE after it is created. Also we need to prevent some rogues creating malicious environment.
  • ARMv9 Confidential Computing Architecture (CCA)
  • Intel Software Guard eXtensions (SGX)
  • AMD SEV
  • IntelTDX

Two main adversaries considered in the TEE threat model

  • Privileged attackers like system software if OS is not trusted.
  • Physical attackers

Key Primitives of TEE

  • Software Attestation
  • Run-time Protection
  • Sealing
TEE Types
 
 
 
TEE Usages
 
 
 
Trusted execution environment
A trusted execution environment (TEE) is a secure area of a main processor. It guarantees code and data loaded inside to be protected with respect to confidentiality and integrity. Data integrity prevents unauthorized entities from outside the TEE from altering data, while code integrity prevents code in the TEE from being replaced or modified by unauthorized entities, which may also be the computer owner itself as in certain DRM schemes described in SGX. This is done by implementing unique, immutable, and confidential architectural security such as Intel Software Guard Extensions (Intel SGX) which offers hardware-based memory encryption that isolates specific application code and data in memory. Intel SGX allows user-level code to allocate private regions of memory, called enclaves, which are designed to be protected from processes running at higher privilege levels.[1][2][3] A TEE as an isolated execution environment provides security features such as isolated execution, integrity of applications executing with the TEE, along with confidentiality of their assets.[4] In general terms, the TEE offers an execution space that provides a higher level of security for trusted applications running on the device than a rich operating system (OS) and more functionality than a 'secure element' (SE).

TEE is fake

New physical attacks are quickly diluting secure enclave defenses from Nvidia, AMD, and Intel
On-chip TEEs withstand rooted OSes but fall instantly to cheap physical attacks.
New physical attacks are quickly diluting secure enclave defenses from Nvidia, AMD, and Intel
 
 

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