CVE-2026-20856 HIGH

CVE-2026-20856: Windows Server Update Service (WSUS) Remote Code Execution Vulnerability

Vendor Microsoft
Product Windows 10 Version 1607
Weakness CWE-20 · Input validation
Published January 13, 2026
Last update April 1, 2026
View on NVD All CVEs

CVSS base score

8.1/10
Attack vector Network
Attack complexity High
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

What the vulnerability does

01Description

Improper input validation in Windows Server Update Service allows an unauthorized attacker to execute code over a network.

Key dates

02Disclosure timeline

January 13, 2026 CVE published
April 1, 2026 Record updated