CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
NONE
AV:L/AC:L/Au:N/C:P/I:N/A:N
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
Percentile
5.1%
Bulletin ID: AMD-SB-1013 **Potential Impact:**Information Disclosure **Severity:**Medium
AMD received notification of a potential security vulnerability from a team of researchers led by Professor Yinqian Zhang from Southern University of Science and Technology (SUSTech). A paper titled “CIPHERLEAKS: Breaking Constant-time Cryptography on AMD SEV via Ciphertext Side Channels” was submitted and accepted for the Usenix Security 2021 conference in August.
CVE-2020-12966
AMD EPYC™ Processors contain an information disclosure vulnerability in the Secure Encrypted Virtualization with Encrypted State (SEV-ES) and Secure Encrypted Virtualization with Secure Nested Paging (SEV-SNP). A local authenticated attacker could potentially exploit this vulnerability leading to leaking guest data by the malicious hypervisor.
1st/2nd/3rd Gen AMD EPYC™ Processors
AMD EPYC™ Embedded Processors
AMD has developed mitigation in the VMSA Register Protection feature to help protect against a malicious hypervisor. The mitigation is available for enablement in 3rd Gen AMD EPYC™ processors and requires the use of SEV-SNP, which is supported on 3rd Gen AMD EPYC™. The update has been released as part of MilanPI-SP3_1.0.0.5.
Prior generations of AMD EPYC™ do not support SEV-SNP.
For earlier AMD EPYC™ products, AMD recommends following security best practices for helping protect against malicious hypervisor attacks. For additional information on SEV-SNP and SEV/SEV-ES please refer to our white paper in the References Section of this document.
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
NONE
Availability Impact
NONE
AV:L/AC:L/Au:N/C:P/I:N/A:N
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
Percentile
5.1%