Check Point Advisories

Microsoft Windows Spoofing (CVE-2026-20872)

Vulnerability
Protection

Check Point Reference:	CPAI-2026-0561
Date Published:	2 Feb 2026
Severity:	Medium
Last Updated:	Monday 02 February, 2026
Source:
Industry Reference:	CVE-2026-20872
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	Microsoft Windows 10 1607 and prior to 10.0.14393.8783 Microsoft Windows 10 1809 and prior to 10.0.17763.8276 Microsoft Windows 10 21H2 and prior to 10.0.19044.6809 Microsoft Windows 10 22H2 and prior to 10.0.19045.6809 Microsoft Windows 11 23H2 and prior to 10.0.22631.6491 Microsoft Windows 11 24H2 and prior to 10.0.26100.7623 Microsoft Windows 11 25H2 and prior to 10.0.26200.7623 Microsoft Windows Server 2008 SP2 Microsoft Windows Server 2008 R2 SP1 Microsoft Windows Server 2012 Microsoft Windows Server 2012 R2 Microsoft Windows Server 2016 and prior to 10.0.14393.8783 Microsoft Windows Server 2019 and prior to 10.0.17763.8276 Microsoft Windows Server 2022 and prior to 10.0.20348.4648 Microsoft Windows Server 2022 23H2 and prior to 10.0.25398.2092 Microsoft Windows Server 2025 and prior to 10.0.26100.32230
Vulnerability Description	A spoofing vulnerability in Microsoft Windows allows an unauthorized attacker to perform spoofing over a network.

Protection Overview

This protection detects attempts to exploit this vulnerability.

In order for the protection to be activated, update your Security Gateway product to the latest IPS update. For information on how to update IPS, go to SBP-2006-05, click on Protection tab and select the version of your choice.

Security Gateway R81 / R80 / R77 / R75

In the IPS tab, click Protections and find the Microsoft Windows Spoofing (CVE-2026-20872) protection using the Search tool and Edit the protection's settings.
Install policy on all Security Gateways.

This protection's log will contain the following information:

Attack Name: Microsoft Windows Operating System.
Attack Information: Microsoft Windows Spoofing (CVE-2026-20872)