JPCERT-AT-2026-0017
JPCERT/CC
2026-06-10

I. Overview

Microsoft has released June 2026 Security Updates to address the vulnerabilities in their products. Attackers leveraging these vulnerabilities may be able to execute arbitrary code remotely without authentication, etc.

Microsoft Corporation
June 2026 Security Updates
https://msrc.microsoft.com/update-guide/en-US/releaseNote/2026-Jun

Microsoft has announced that the following vulnerability, disclosed on May 14, has been exploited in the wild. Please refer to the latest information provided by Microsoft and implement the measures described in "II. Solution."

CVE-2026-42897
Microsoft Exchange Server Spoofing Vulnerability
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-42897

II. Solution

Please apply the security update programs through Microsoft Update, Windows Update, etc.

Microsoft Update Catalog
https://www.catalog.update.microsoft.com/

Windows Update: FAQ
https://support.microsoft.com/en-us/help/12373/windows-update-faq

III. References

Microsoft Corporation
Release Notes
https://msrc.microsoft.com/update-guide/

If you have any information regarding this alert, please contact JPCERT/CC.

JPCERT Coordination Center (Cyber Security Coordination Group)
MAIL: ew-info@jpcert.or.jp
https://www.jpcert.or.jp/english/