CVE-2026-20812

Published: Jan 13, 2026Modified: Jan 14, 2026

6.5

Vector

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

Exploitability: 2.8 / Impact: 3.6

Source: secure@microsoft.com

Description

Improper input validation in Windows LDAP - Lightweight Directory Access Protocol allows an authorized attacker to perform tampering over a network.

Affected (14)

Products: Microsoft: Windows 10 1607, Windows 10 1809, Windows 10 21h2, Windows 10 22h2, Windows 11 23h2, Windows 11 24h2, Windows 11 25h2, Windows Server 2016, Windows Server 2019, Windows Server 2022, Windows Server 2022 23h2, Windows Server 2025

12 products

Windows 10 1607

Windows 10 1809

Windows 10 21h2

Windows 10 22h2

Windows 11 23h2

Windows 11 24h2

Windows 11 25h2

Windows Server 2016

Windows Server 2019

Windows Server 2022

Windows Server 2022 23h2

Windows Server 2025

Configuration A

14 vulnerable

Vulnerable Software	Affected Versions
Microsoft Windows 10 1607	Before 10.0.14393.8783
Microsoft Windows 10 1607	Before 10.0.14393.8783
Microsoft Windows 10 1809	Before 10.0.17763.8276
Microsoft Windows 10 1809	Before 10.0.17763.8276
Microsoft Windows 10 21h2	Before 10.0.19044.6809
Microsoft Windows 10 22h2	Before 10.0.19045.6809
Microsoft Windows 11 23h2	Before 10.0.22631.6491
Microsoft Windows 11 24h2	Before 10.0.26100.7623
Microsoft Windows 11 25h2	Before 10.0.26200.7623
Microsoft Windows Server 2016	Before 10.0.14393.8783
Microsoft Windows Server 2019	Before 10.0.17763.8276
Microsoft Windows Server 2022	Before 10.0.20348.4648
Microsoft Windows Server 2022 23h2	Before 10.0.25398.2092
Microsoft Windows Server 2025	Before 10.0.26100.32230

Related CWEs

Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

References (1)

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20812

Source: secure@microsoft.com

Vendor Advisory

Timeline

No history available yet.