AMD EPYC 9004 Processors Secure Encrypted Virtualization improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.1$0-$5k0.00+

Summaryinfo

A vulnerability, which was classified as very critical, has been found in AMD EPYC 9004 Processors, EPYC 7003 Processors, EPYC 9005 Processors, EPYC 8004 Processors, EPYC 8005 Processors, EPYC Embedded 7003 Processors, EPYC Embedded 9004 Processors, EPYC Embedded 8004 Processors and EPYC Embedded 9005 Processors. The affected element is an unknown function of the component Secure Encrypted Virtualization. Performing a manipulation results in improper authentication. This vulnerability is reported as CVE-2026-40668. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as very critical has been found in AMD EPYC 9004 Processors, EPYC 7003 Processors, EPYC 9005 Processors, EPYC 8004 Processors, EPYC 8005 Processors, EPYC Embedded 7003 Processors, EPYC Embedded 9004 Processors, EPYC Embedded 8004 Processors and EPYC Embedded 9005 Processors. This affects an unknown functionality of the component Secure Encrypted Virtualization. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Authentication bypass by spoofing in AMD Secure Encrypted Virtualization (SEV) firmware could allow a malicious hypervisor to request attestation reports for VMPL 0.

The advisory is shared at amd.com. This vulnerability is uniquely identified as CVE-2026-40668 since 04/14/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are required for exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/10/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 9.1
VulDB Meta Temp Score: 9.1

VulDB Base Score: 9.1
VulDB Temp Score: 9.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

04/14/2026 CVE reserved
11/10/2026 +210 days Advisory disclosed
11/10/2026 +0 days VulDB entry created
11/10/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: amd.com
Status: Confirmed

CNA: AMD
CVE: CVE-2026-40668 (🔒)

GCVE (CVE): GCVE-0-2026-40668
GCVE (VulDB): GCVE-100-435177

Entryinfo

Created: 11/10/2026 23:38
Changes: 11/10/2026 23:38 (63)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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