Tuesday 8 September 2026

September 2026: is it safe to deploy?

What Microsoft fixed, how urgent it is, and whether anything broke, per Windows version, from Microsoft's release tables, release health, MSRC, CISA, and what the community reports.

← Aug 2026 Oct 2026 →

Superseded

Newer updates replace September 2026.

Microsoft fixed 998 CVEs, 132 critical and 2 exploited; no open known issues found in the current public evidence; out-of-band fixes followed on 14 Sep. See November 2026 Patch Tuesday.

26 of these CVEs were added after 8 Sep 2026; the release-day timeline keeps the original publication dates.

ChangeIntel's reading of public signals, not advice; check Microsoft's guidance and test before you deploy. Terms

Microsoft CVEs: 998
Critical: 132
Exploited fixed: 2
In CISA KEV: 2
Open known issues: 0
Out-of-band: 8

Release calendar · October 2023

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KB5031455 · Win 11 23H2

Patch Tuesday and security (B) releasesPreview (D) releasesOut-of-band releases.NET Framework servicing packagesEdge, Office, Teams, Defender and server releasesAll product versions