Keycloak 21.0 End of Life
Support dates, vulnerabilities published since end of life, and upgrade guidance — rebuilt from live data.
Keycloak 21.0 reached end of life on 19 Apr 2023. It no longer receives security fixes.
Support timeline
Official dates, read directly from github.com.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 23 Feb 2023 | — |
| End of life | 19 Apr 2023 | 3.3 years ago |
| Latest release | 21.0.2 · 30 Mar 2023 | final |
The cost of staying: CVEs since end of life
27 Keycloak vulnerabilities have been published since 19 Apr 2023. All were fixed in supported branches — 21.0 received none of them. Source: NVD.
Keycloak CVEs published since 21.0's EOL, by year
1 of the 27 are rated critical · data refreshed 2026-08-09
Published 7 Jul 2023 · rated critical — fixed in supported branches only, never in 21.0. Details
Published 12 Sept 2023 · rated high — fixed in supported branches only, never in 21.0. Details
Published 5 Mar 2026 · rated high — fixed in supported branches only, never in 21.0. Details
This product uses data from the NVD API but is not endorsed or certified by the NVD.
Where to go from 21.0
Recommended target: Keycloak 26.7.
The newest actively supported branch is Keycloak 26.7 (latest release 26.7.1).
Frequently asked questions
Is Keycloak 21.0 still safe to use?
No. Keycloak 21.0 stopped receiving security fixes on 19 Apr 2023. Since then, 27 Keycloak vulnerabilities have been published and fixed in supported branches — Keycloak 21.0 received none of those fixes.
Can I still download Keycloak 21.0?
Yes — the final release (21.0.2) generally remains available from vendor archives and OS package mirrors, but installing it means running software with known, unpatched vulnerabilities.
What should I upgrade Keycloak 21.0 to?
Upgrade to Keycloak 26.7, the newest actively supported branch.