Three potential vulnerabilities in Secure Encrypted Virtualization – Secure Nested Paging (SEV-SNP) could allow an attacker to read or corrupt the memory of a guest VM.
To establish an isolated execution environment, (SEV-SNP) adds robust memory integrity protection to prevent malicious hypervisor-based attacks, including data replay, memory remapping, and more.
AMD fixes multiple memory flaws and recommends upgrading to the appropriate Platform Initialization (PI) firmware version.
Details Of Vulnerabilities
CVE-2024-21978- Improper Input Validation
With a Medium severity CVSS base score of 6.0, improper input validation in SEV-SNP could enable a malicious hypervisor to read or overwrite guest memory, which could result in data corruption or leaking.
CVE-2024-21980 – Improper Restriction of Write Operations
This issue has a CVSS base score of 7.9, indicating a high severity. A malicious hypervisor may be able to overwrite a guest’s memory or UMC seed if write operations in SNP firmware are improperly restricted. The flaw could lead to a loss of confidentiality and integrity.
CVE-2023-31355 – Improper Restriction of Write Operations
With a CVSS base score of 6.0, this flaw is classified as Medium severity. A malicious hypervisor may be able to overwrite a guest’s UMC seed through improper restriction of write operations in SEV-SNP firmware. Hence, it allows the reading of memory from a decommissioned guest. Tom Dohrmann reported the vulnerabilities.
Affected Products And Fixes Available
-
3rd Gen AMD EPYC™ Processors formerly codenamed “Milan” – Update to MilanPI 1.0.0.D
-
4th Gen AMD EPYC™ Processors formerly codenamed “Genoa” – Update to GenoaPI 1.0.0.C
-
AMD EPYC™ Embedded 7003 – Update to EmbMilanPI-SP3 1.0.0.9
-
AMD EPYC™ Embedded 9003 – Update to EmbGenoaPI-SP5 1.0.0.7
AMD advises upgrading to the most recent versions to defend against the numerous memory vulnerabilities.
Download Free Cybersecurity Planning Checklist for SME Leaders (PDF) – [Free Download](https://go.cynet.com/cybersecurity-planning-checklist-2024?utm_source=cyber_security_news&utm_medium=display_ad&utm_campaign=Q3-sponsored-content)