Is Kotlin 2.3.21 patched?
Current stable (2.4.0): 100/100
Summary iPlain-English security status for Kotlin 2.3.21, built from its CVEs, active-exploitation data, end-of-life date and latest release.
Kotlin 2.3.21 is part of the 2.3 release line. No known vulnerabilities affect it in our data. The 2.3 line reached end-of-life on 2026-06-03, so it no longer receives security patches. The latest supported Kotlin release is 2.4.0.
Known issues affecting 2.3.21
None found for this version. ✓
Other Kotlin versions
Check another release line of Kotlin.
Frequently asked
Is Kotlin 2.3.21 patched?
Kotlin 2.3.21 is end-of-life and no longer receives security patches. Move to 2.4.0.
When does Kotlin 2.3 reach end-of-life?
Kotlin 2.3 reached end-of-life on 2026-06-03 and no longer receives security patches.
What is the latest version of Kotlin?
The latest supported Kotlin release is 2.4.0.
Is Kotlin 2.3.21 still receiving security updates?
No — Kotlin 2.3.21 is on the 2.3 line, which reached end-of-life on 2026-06-03 and no longer receives security updates. Upgrade to 2.4.0 or later to stay supported.
Informational only, from public data (NVD · CISA KEV · EPSS · endoflife.date), and can lag or miss vendor-specific fixes. Always confirm against JetBrains's official advisory before you patch or upgrade — Kotlin official site ↗