Alert: Notice Regarding Microsoft Security Updates for October 2026 (Public)

JPCERT-AT-2026-0031 JPCERT/CC October 14, 2026 Microsoft Corporation October 2026 Security Updates (Monthly) https://www.microsoft.com/msrc/blog/2026/10/202610-security-update Microsoft has announced that the following vulnerability among these vulnerabilities is being exploited. Please check the latest information provided by Microsoft and implement "II. Countermeasures." CVE-2026-96951 Vulnerability to Bypass Windows Shell Security Features https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96951 Microsoft Update Catalog https://www.catalog.update.microsoft.com/ Windows Update: Frequently Asked Questions https://support.microsoft.com/ja-JP/help/12373/windows-update-faq Microsoft Corporation October 2026 Security Updates https://msrc.microsoft.com/update-guide/ja-jp/releaseNote/2026-Oct Microsoft Corporation Security Update Guide https://msrc.microsoft.com/update-guide/ If you have any information regarding this matter, please contact JPCERT/CC. Japan Computer Emergency Response Team Coordination Center (JPCERT/CC) Cybersecurity Coordination Group Email: ew-info@jpcert.or.jp JPCERT/CC October 14, 2026 I. Overview Microsoft has released the October 2026 security updates to fix vulnerabilities in its products. If these vulnerabilities are exploited, it may be possible to execute arbitrary code remotely or bypass security features. Microsoft Corporation October 2026 Security Updates (Monthly) https://www.microsoft.com/msrc/blog/2026/10/202610-security-update Microsoft has announced that the following vulnerability among these vulnerabilities is being exploited. Please check the latest information provided by Microsoft and implement "II. Countermeasures." CVE-2026-96951 Vulnerability to Bypass Windows Shell Security Features https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96951 II. Countermeasures Please apply the security updates using Microsoft Update or Windows Update. Microsoft Update Catalog https://www.catalog.update.microsoft.com/ Windows Update: Frequently Asked Questions https://support.microsoft.com/ja-JP/help/12373/windows-update-faq III. Reference Information Microsoft Corporation October 2026 Security Updates https://msrc.microsoft.com/update-guide/ja-jp/releaseNote/2026-Oct Microsoft Corporation Security Update Guide https://msrc.microsoft.com/update-guide/ If you have any information regarding this matter, please contact JPCERT/CC. Japan Computer Emergency Response Team Coordination Center (JPCERT/CC) Cybersecurity Coordination Group Email: ew-info@jpcert.or.jp