Intel, AMD processor-stored secrets threatened by novel TEE.Fail intrusion

Intel's Software Guard Extensions and Trust Domain Extensions, as well as AMD's Secure Encrypted Virtualization with Secure Nested Paging, which are DDR5 CPUs' trusted execution environments, could expose secrets through the new TEE.Fail side-channel attack, reports The Hacker News.

Utilization of an interposition device with cheap off-the-shelf electronics has allowed cryptographic key extraction from Intel TDX and AMD SEV-SNP with Ciphertext Hiding, a report from Georgia Tech, Purdue University, and Synkhronix researchers showed.

Researchers discovered the deterministic nature of the AES-XTS encryption mode used by Intel and AMD chips, which has allowed physical memory interposition intrusions. Further analysis revealed that TEE.Fail could be harnessed to obtain attestation keys that could breach Nvidia's GPU Confidential Computing and facilitate subsequent execution of artificial intelligence workloads.

Neither Intel nor AMD intends to issue mitigations for the issue, which they noted to be out-of-scope for their respective chips' TEEs. Such findings follow the discovery of a WireTap attack against systems running on DDR4 memory.