AMD SEV firmware: expected-behavior violation lets a malicious hypervisor bypass RMP on EPYC 9005

Impact

A malicious hypervisor can bypass Reverse Map Table protections through an expected-behavior violation in SEV firmware. That costs SEV-SNP guests their memory integrity guarantee. Only EPYC 9005 (Turin), including Embedded 9005, is listed. This flaw has a different root cause from CVE-2025-0027 in the same bulletin and affects fewer products. It matters wherever confidential VMs are offered on Turin GPU hosts.

Who can reach it

Requires control of the hypervisor on an EPYC 9005 host. Not reachable from a guest or the network.

What to do

Apply the SEV firmware fix from AMD-SB-3037 for EPYC 9005. The record gives no fixed version or delivery mechanism. Get the platform firmware release from the bulletin and your OEM, and schedule host maintenance for SEV-SNP nodes.

References

Related entries

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