Supermicro is aware of the potential vulnerabilities in AMD EPYC™ malicious hypervisor can undermine the integrity protections of AMD Secure Encrypted Virtualization – Secure Nested Paging (SEV-SNP) by forcing the AMD Security Processor (ASP) to operate without cache coherency with system memory. AMD released mitigations for this vulnerability. This vulnerability affects BIOS in Supermicro H13 and H14 products.
CVE:
- CVE-2025-54509
- Severity: Medium
Findings:
A hypervisor-controlled system setting allows reconfiguration of how the ASP’s memory requests interact with the CPU caches. By turning off coherency, the ASP may read stale data from DRAM when copying pages and updating associated metadata, causing recent in-CPU-cache updates from the guest to be lost. This could potentially undermine SEV-SNP’s guest integrity guarantees and allow data corruption.
Successful exploitation requires a malicious or compromised hypervisor with the ability to change the relevant system setting and to trigger ASP-managed memory operations. In addition, practical exploitation depends on a race condition, requiring precise timing to impact guest integrity.
| CVE ID | Description |
|---|---|
| CVE-2025-54509 | Improper access control for register interface in the input-output memory management unit (IOMMU) could allow a privileged attacker to cause non-coherent access by the AMD Secure Processor (ASP) potentially resulting in loss of integrity. |
Affected products:
Supermicro BIOS on the server H13, and H14 motherboards.
| AMD Motherboard Generation | BIOS Version with Fix |
|---|---|
| H13 – H13SVW-N/NT – EPYC™ 8004 series | v 1.6 |
| H13 – H13SSW – EPYC 9004/9005 series | v 3.8 |
| H13 – H13DSH – EPYC 9004/9005 series | v 3.8a |
| H13 – H13DSG-O-CPU – EPYC 9004/9005 series | v 3.9 |
| H13 – H13SST-G/GC – EPYC 9004/9005 series | v 3.7 |
| H13 – H13SSL-N/NT – EPYC 9004/9005 series | v 3.8 |
| H13 – H13SSH – EPYC 9004/9005 series | v 3.9 |
| H13 – H13SSH-E – EPYC 9004/9005 series | v 3.9 |
| H13 – H13DSG-O-CPU-D – EPYC 9004 series | v 3.8a |
| H13 – H13SSF – EPYC 9004/9005 series | v 3.8 |
| H13 – H13DSG-OM – EPYC 9004/9005 series | v 3.9 |
| H14 – H14DSH – EPYC 9004/9005 series | v 1.8a |
| H14 – H14SST-G – EPYC 9004/9005 series | v 1.9 |
| H14 – H14SST-GE – EPYC 9005 series | v 1.1b |
| H14 – H14DSG-OD – EPYC 9004/9005 series | v 1.9 |
| H14 – H14SHM – EPYC 9004/9005 series | v 1.8 |
| H14 – H14DST-F/FL – EPYC 9005 series | v 1.8 |
| H14 – H14DSG-O-CPU – EPYC 9004/9005 series | v 1.8 |
| H14 – H14SSL-N/NT – EPYC 9004/9005 series | v 2.0 |
| H14 – H14DSG-OM – EPYC 9004/9005 series | v 1.3 |
| H14 – H14SSF – EPYC 9005 series | v 1.0 |
Remediation:
- All affected Supermicro motherboard SKUs will require a BIOS update to mitigate this potential vulnerability.
- Updated BIOS firmware has been created to mitigate this potential vulnerability. Supermicro is currently testing and validating affected products. Please check Release Notes for the resolution.