Microsoft's July 2026 security updates address two vulnerabilities, CVE-2026-56164 (CVSS 5.3) in SharePoint Server and CVE-2026-56155 (CVSS 7.8) in Active Directory Federation Services, which are being actively exploited to enable privilege escalation. Affected SharePoint Server versions prior to 16.0.19725.20434 are vulnerable, requiring an update to that specific version. The solution is to apply the relevant security updates via Microsoft Update, Windows Update, or the Microsoft Update Catalog.
JPCERT-AT-2026-0020 JPCERT/CC 2026-07-15 I. Overview Microsoft has released July 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 July 2026 Security Updates https://msrc.microsoft.com/update-guide/en-US/releaseNote/2026-Jul According to Microsoft, among the vulnerabilities, the following vulnerabilities have been confirmed to be exploited in the wild. Please refer to the latest information provided by Microsoft and implement the measures described in "II. Solution." CVE-2026-56164 Microsoft SharePoint Server Elevation of Privilege Vulnerability https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56164 CVE-2026-56155 Active Directory Federation Services Elevation of Privilege Vulnerability https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-56155 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/ Top