CVE-2026-21239

HighCVSS 7.8/10Last modified Jun 17, 2026

Description

Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

Metrics

CVSS 3.1 7.8/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-122CWE-787

Affected software

No affected versions have been published.

Timeline

Published
Feb 10, 2026
Last modified
Jun 17, 2026
NVD status
Analyzed

Related CVEs from 2026

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CVE-2026-21239: High severity, CVSS 7.8 | Vulnix