AMD EPYC 9004 Processors Reverse Map Table off-by-one

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 was found in AMD EPYC 9004 Processors, EPYC 7003 Processors, EPYC 8004 Processors, EPYC Embedded 7003 Processors, EPYC Embedded 9004 Processors and EPYC Embedded 8004 Processors. It has been rated as very critical. This impacts an unknown function of the component Reverse Map Table. This manipulation causes off-by-one. The identification of this vulnerability is CVE-2026-40669. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as very critical was found in AMD EPYC 9004 Processors, EPYC 7003 Processors, EPYC 8004 Processors, EPYC Embedded 7003 Processors, EPYC Embedded 9004 Processors and EPYC Embedded 8004 Processors. Affected by this vulnerability is an unknown function of the component Reverse Map Table. The manipulation with an unknown input leads to a off-by-one vulnerability. The CWE definition for the vulnerability is CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

An off-by-one error in AMD Secure Encrypted Virtualization (SEV) firmware could allow an attacker with hypervisor access to corrupt the Reverse Map Table (RMP) table, potentially resulting in loss of guest memory integrity.

The advisory is shared at amd.com. This vulnerability is known as CVE-2026-40669 since 04/14/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are needed 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

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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: Off-by-one
CWE: CWE-193 / CWE-189
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-2026-40669 (🔒)

GCVE (CVE): GCVE-0-2026-40669
GCVE (VulDB): GCVE-100-435169

Entryinfo

Created: 11/10/2026 23:36
Changes: 11/10/2026 23:36 (63)
Complete: 🔍
Cache ID: 216::103

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

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