Intel TXT

Intel TXT establishes a hardware-based root of trust to verify platform integrity from boot-up through runtime.

Intel TXT uses the SENTER instruction to trigger a Measured Launch Environment (MLE) that anchors platform security in the silicon. It leverages a Trusted Platform Module (TPM) and Authenticated Code (AC) modules to cryptographically measure the BIOS, firmware, and hypervisor. This creates a verifiable chain of trust: detecting rootkits or firmware tampering before the OS even initializes. By comparing these measurements against known-good values, TXT ensures that sensitive workloads execute only on a platform with a proven (untampered) state.

https://www.intel.com/content/www/us/en/architecture-and-technology/trusted-execution-technology/trusted-execution-technology-security-overview.html