PT-2026-7343 · Microsoft · Windows Kernel+1

Published 2026-02-10 · Updated 2026-02-11 · CVE-2026-21239

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Windows Kernel (affected versions not specified)

Description A heap-based buffer overflow exists in the Windows Kernel. This issue allows a locally authenticated attacker to gain elevated privileges. The vulnerability enables attackers to affect the system.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Memory Corruption

Heap Based Buffer Overflow

Weakness Enumeration

CWE-787

CWE-122

Related Identifiers

BDU:2026-01802

CVE-2026-21239

Affected Products

Windows

Windows Kernel

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-21239 · Security Note
• https://osv.dev/vulnerability/CVE-2026-21239 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21239 · Vendor Advisory
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-21239 · Security Note
• https://bdu.fstec.ru/vul/2026-01802 · Security Note
• https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2026-21239 · Vendor Advisory
• https://t.me/avleonovcom/1631 · Telegram Post