Microsoft’s September patch fixed 974 vulnerabilities, a tenfold increase from previous years; the high-risk CVE-2026-81963 has been exploited by hackers.

On September 8, 2026, Microsoft fixed a total of 974 security vulnerabilities in all its products, including Windows 10 and Windows 11 (including versions 24H2 and 25H2), during the Patch Tuesday event. This represents a 1032.6% increase compared to the same period last year. Of these, 723 vulnerabilities were fixed for Windows systems, mainly involving improper link resolution before file access, Windows Hello, biometric services, and basic components such as the graphics kernel. The most notable vulnerability, CVE-2026-81963, was confirmed to have been exploited by hackers. Microsoft recommends that users install and upgrade as soon as possible. Jeremy Chapman, director of Microsoft 365, said that to reduce the time exposed to risk, the delay period for recommended quality updates has been tightened to at least 3 days.