Description

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

INFO

Published Date :

2026-01-13T17:56:30.668Z

Last Modified :

2026-01-20T17:34:50.060Z

Source :

microsoft
AFFECTED PRODUCTS

The following products are affected by CVE-2026-20856 vulnerability.

Vendors Products
Microsoft
  • Windows 10 1607
  • Windows 10 1809
  • Windows 10 21h2
  • Windows 10 21h2
  • Windows 10 22h2
  • Windows 10 22h2
  • Windows 11 23h2
  • Windows 11 23h2
  • Windows 11 24h2
  • Windows 11 24h2
  • Windows 11 25h2
  • Windows 11 25h2
  • Windows Server 2012
  • Windows Server 2012 R2
  • Windows Server 2016
  • Windows Server 2019
  • Windows Server 2022
  • Windows Server 2022 23h2
  • Windows Server 2025
  • Windows Server 23h2
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-20856.

URL Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20856 cve-icon cve-icon
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CVSS Vulnerability Scoring System

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