Tuesday 9 December 2025

December 2025: 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.

← Nov 2025 Jan 2026 →

Superseded

Newer updates replace December 2025.

The CVEs it fixes are unknown; no open known issues found in the current public evidence; out-of-band fixes followed on 18 Dec. See November 2026 Patch Tuesday.

MSRC's December 2025 security update document isn't collected.

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

Microsoft CVEs: Unknown
Exploited fixed: Unknown
In CISA KEV: Unknown
Open known issues: 0
Out-of-band: 3

Release calendar · March 2029

Thu 1 Mar

Fri 2 Mar

Sat 3 Mar

Sun 4 Mar

Mon 5 Mar

Tue 6 Mar

Wed 7 Mar

Thu 8 Mar

Fri 9 Mar

Sat 10 Mar

Sun 11 Mar

Mon 12 Mar

Tue 13 Mar

Patch Tuesday

Wed 14 Mar

Thu 15 Mar

Fri 16 Mar

Sat 17 Mar

Sun 18 Mar

Mon 19 Mar

Tue 20 Mar

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Mon 26 Mar

Tue 27 Mar

Wed 28 Mar

Thu 29 Mar

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Sat 31 Mar

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