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2 vulnerabilities found for Windows OS by Microsoft

CVE-2026-2636 (GCVE-0-2026-2636)

Vulnerability from nvd – Published: 2026-02-25 18:57 – Updated: 2026-02-26 15:56
VLAI?
Title
Denial of Service in Microsoft OS
Summary
This vulnerability is caused by a CWE‑159: "Improper Handling of Invalid Use of Special Elements" weakness, which leads to an unrecoverable inconsistency in the CLFS.sys driver. This condition forces a call to the KeBugCheckEx function, allowing an unprivileged user to trigger a system crash. Microsoft silently fixed this vulnerability in the September 2025 cumulative update for Windows 11 2024 LTSC and Windows Server 2025. Windows 25H2 (released in September) was released with the patch. Windows 1123h2 and earlier versions remain vulnerable.
Severity ?
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-159 - Improper Handling of Invalid Use of Special Elements
Assigner
References
Impacted products
Vendor Product Version
Microsoft Windows OS Affected: 0 , < 25H2 (semver)
Affected: 0 , ≤ 1123h2 (semver)
Create a notification for this product.
Show details on NVD website
To clipboard 

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CVE-2026-2636 (GCVE-0-2026-2636)

Vulnerability from cvelistv5 – Published: 2026-02-25 18:57 – Updated: 2026-02-26 15:56
VLAI?
Title
Denial of Service in Microsoft OS
Summary
This vulnerability is caused by a CWE‑159: "Improper Handling of Invalid Use of Special Elements" weakness, which leads to an unrecoverable inconsistency in the CLFS.sys driver. This condition forces a call to the KeBugCheckEx function, allowing an unprivileged user to trigger a system crash. Microsoft silently fixed this vulnerability in the September 2025 cumulative update for Windows 11 2024 LTSC and Windows Server 2025. Windows 25H2 (released in September) was released with the patch. Windows 1123h2 and earlier versions remain vulnerable.
Severity ?
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-159 - Improper Handling of Invalid Use of Special Elements
Assigner
References
Impacted products
Vendor Product Version
Microsoft Windows OS Affected: 0 , < 25H2 (semver)
Affected: 0 , ≤ 1123h2 (semver)
Create a notification for this product.
Show details on NVD website
To clipboard 

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