May 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.
May 2021: public evidence is incomplete.
The CVEs it fixes are unknown; no open known issues found in the current public evidence.
MSRC's May 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
- 0
What to deploy, per Windows version
All 10 versions:Urgency: UnknownMSRC's May 2021 document isn't collected, so the CVEs it fixes are unknownNo known issues linked to this update were identified in the collected Windows release health data
Verdicts read public signals for each update: fixed CVEs and their exploitation, known issues, and out-of-band follow-ups. Open an update for every reason and its builds.