CVE-2026-66334 - Vulnerability Details - OpenCVE

AMI APTIOV contains vulnerabilities in BIOS where
privileged users may cause the “Out-of-Bounds Write” by
local access. Successful exploitation of this vulnerability may lead to a
denial of service during firmware update processing, such as a crash or failed
update if the out-of-bounds write hits unmapped memory. It could also impact Integrity, and Availability.

Attack Vector Local

Attack Complexity Low

Privileges Required High

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

No data.

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://go.ami.com/hubfs/Security%20Advisories/2026/AMI-SA-2026003.pdf

History

Tue, 10 Nov 2026 16:30:00 +0000

Type	Values Removed	Values Added
Description		AMI APTIOV contains vulnerabilities in BIOS where privileged users may cause the “Out-of-Bounds Write” by local access. Successful exploitation of this vulnerability may lead to a denial of service during firmware update processing, such as a crash or failed update if the out-of-bounds write hits unmapped memory. It could also impact Integrity, and Availability.
Title		OFBD SMM Write Validation Issues
Weaknesses		CWE-787
References		https://go.ami.com/hubfs/Security%20Advisories/2026/AMI-SA-2026003.pdf
Metrics		cvssV4_0 `{'score': 6.8, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: AMI

Published: 2026-11-10T16:22:38.610Z

Updated: 2026-11-10T16:22:38.610Z

Reserved: 2026-07-24T21:31:28.218Z

Link: CVE-2026-66334

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-11-10T17:17:46.733

Modified: 2026-11-10T17:17:46.733

Link: CVE-2026-66334

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-787

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