Tuesday 14 December 2021

December 2021: 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 2021 Jan 2022 →

Evidence incomplete

December 2021: public evidence is incomplete.

The CVEs it fixes are unknown; no open known issues found in the current public evidence; out-of-band fixes followed on 4 Jan, 5 Jan.

MSRC's December 2021 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 · February 2025

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