AMD EPYC 7451

Secure Encrypted Virtualization (SEV) on Advanced Micro Devices (AMD) Platform Security Processor (PSP; aka AMD Secure Processor or AMD-SP) 0.17 build 11 and earlier has an insecure cryptographic implementation.

Insufficient input validation in the ASP Bootloader may enable a privileged attacker with physical access to expose the contents of ASP memory potentially leading to a loss of confidentiality.

In SEV guest VMs, the CPU may fail to flush the Translation Lookaside Buffer (TLB) following a particular sequence of operations that includes creation of a new virtual machine control block (VMCB). The failure to flush the TLB may cause the microcode to use stale TLB translations which may allow for disclosure of SEV guest memory contents. Users of SEV-ES/SEV-SNP guest VMs are not impacted by this vulnerability.