CVE 2026 97631

access.redhat.com • October 28, 2026

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A flaw was found in EDK2. Due to improper buffer size calculations in the firmware, an unauthenticated remote attacker can trigger a buffer overflow. Successful exploitation can lead to arbitrary code execution or cause a denial of service (DoS).

Bugzilla 2559129 : edk2: Pre-boot RCE in EDK II PXE driver

CWE-787 : Out-of-bounds Write

Common Vulnerability Scoring System (CVSS) Score Details

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The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red Hat: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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The full story

This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.

Critical UEFI Flaw CVE-2026-97631 Exposes Servers to Pre-Boot Code Execution A critical vulnerability, CVE-2026-97631, has been identified in the EDK II firmware used by many servers, allowing unauthenticated attackers to execute arbitrary code during network boot before Secure Boot protections are engaged. The flaw, a buffer overflow in the PXE Base Code driver, scores 9.5 on the CVSS scale and affects systems booting over PXE using ICMP error messages. While the vulnerability was disclosed on October 22, 2026, no stable patches are available as of October 28, 2026, with only development branches containing fixes. Major distributions like Red Hat, SUSE, and Debian have acknowledged the issue but lack immediate solutions. The exposure is significant, particularly for data centers and managed service providers that utilize PXE booting. Exploitation requires knowledge of the specific firmware build, but the risk remains high due to the widespread use of the affected firmware. 18 sources 68

CVE 2026 97631

The full story

Extracted Entities

CWE Weaknesses (1)

Platforms (2)