CVE-2026-97631

EDK2 contains a vulnerability in BIOS where a user may cause “Out-of-bounds Write”, Classic Buffer Overflow, and “Incorrect Calculation of Buffer Size” by remote access. Successful exploitation of this vulnerability can lead to arbitrary code execution. It could also impact Confidentiality, Integrity, and Availability.

CVSS

No CVSS.

References

Link	Resource
https://github.com/tianocore/edk2/security/advisories/GHSA-99cj-7hg9-mp4m
http://www.openwall.com/lists/oss-security/2026/10/28/4
https://arstechnica.com/security/2026/10/code-execution-flaw-in-uefi-firmware-threatens-most-servers-on-planet-earth/
https://github.com/microsoft/mu_basecore/pull/1989
https://github.com/microsoft/mu_basecore/pull/1990
https://news.ycombinator.com/item?id=50265393

Configurations

No configuration.

History

28 Oct 2026, 16:17

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/10/28/4 -

28 Oct 2026, 15:17

Type	Values Removed	Values Added
References		() https://arstechnica.com/security/2026/10/code-execution-flaw-in-uefi-firmware-threatens-most-servers-on-planet-earth/ - () https://github.com/microsoft/mu_basecore/pull/1989 - () https://github.com/microsoft/mu_basecore/pull/1990 - () https://news.ycombinator.com/item?id=50265393 -

22 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 17:17

Updated : 2026-10-30 20:17

NVD link : CVE-2026-97631

Mitre link : CVE-2026-97631

CVE.ORG link : CVE-2026-97631

JSON object : View

Products Affected

No product.

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CWE-131

Incorrect Calculation of Buffer Size

CWE-787

Out-of-bounds Write

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