Patch Tuesday - September 2026
Microsoft's September 2026 Patch Tuesday fixes 999 CVEs, a record, with two zero-day privilege escalation flaws already exploited in the wild.
Microsoft published 974 own-product vulnerabilities plus 25 non-Microsoft CVEs, totaling 999 — the most CVEs Microsoft has ever released in a single day. Two flaws are exploited in the wild: CVE-2026-85880, an out-of-bounds write in Windows ALPC granting SYSTEM privileges, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack also leading to SYSTEM. Chrome's V8 zero-day CVE-2026-85046 was patched in Edge on September 2, but Microsoft had not published a corresponding advisory, leaving uncertainty about other Chromium fixes in Edge. October 14 lifecycle changes end servicing for Windows 11 24H2 Home/Pro, Office 2021, and Exchange Server 2016/2019.
Microsoft patches a record 972 vulnerabilities, 112 of them critical
Microsoft's September Patch Tuesday fixes a record 972 vulnerabilities, 112 rated critical, including two zero-days in Windows components.
Microsoft's September 2026 release patched roughly 972 vulnerabilities (997 including ported Chromium fixes for Edge), a record, with 112 rated critical. Notable flaws include two zero-days: CVE-2026-81963 in the Windows update service and CVE-2026-85880 in the Windows Advanced Local Procedure, with no public information on exploitation breadth. Microsoft has fixed 2,760 vulnerabilities in 2026, more than double last year's total, which ZDI's Dustin Childs attributes to AI-assisted discovery becoming the 'new normal'.