Check Point Advisories

Microsoft Exchange Server Cross-Site Scripting (CVE-2026-42897)

Vulnerability
Protection

Check Point Reference:	CPAI-2026-9752
Date Published:	2 Aug 2026
Severity:	Medium
Last Updated:	Sunday 02 August, 2026
Source:
Industry Reference:	CVE-2026-42897
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?	Microsoft Exchange Server 2016 Cumulative Update 23 15.01.0.0 and later, prior to 15.01.2507.069 Microsoft Exchange Server 2019 Cumulative Update 14 15.02.0.0 and later, prior to 15.02.1544.041 Microsoft Exchange Server 2019 Cumulative Update 15 15.02.0.0 and later, prior to 15.02.1748.046 Microsoft Exchange Server Subscription Edition RTM 15.02.0.0 and later, prior to 15.02.2562.043
Vulnerability Description	A cross-site scripting vulnerability in Microsoft Exchange Server 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 Exchange Server Cross-Site Scripting (CVE-2026-42897) 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: Windows SMB Protection Violation.
Attack Information: Microsoft Exchange Server Cross-Site Scripting (CVE-2026-42897)