Fluent Bit 4.x — End of Life
EOL soonFluent Bit 4.x — All releases
| Version | Released | Active support | EOL date | Latest patch | Status |
|---|---|---|---|---|---|
| 4.2 | Nov 11, 2025 | — | Jun 30, 2026 | 4.2.5 | EOL soon |
| 4.1 | Sep 24, 2025 | — | Feb 11, 2026 | 4.1.2 | EOL |
| 4.0 | Mar 29, 2025 | — | Dec 24, 2025 | 4.0.14 | EOL |
CVEs affecting Fluent Bit 4.x (0)
Fluent Bit 4.x will reach end of life — migrate to Fluent Bit 5.x
Fluent Bit 5.x is the next major release. Plan your upgrade before Fluent Bit 4.x stops receiving security patches.
Frequently asked questions
Is Fluent Bit 4 end of life?
Partially. Some Fluent Bit 4.x releases have reached EOL. Check the version table above for the exact status of each sub-release.
What CVEs affect Fluent Bit 4?
No CVEs are currently tracked for Fluent Bit 4.x in our database. This may mean no vulnerabilities have been recorded yet, or the data is still syncing.
What is the latest Fluent Bit 4 version?
The latest Fluent Bit 4.x patch release is 4.2.5, released on June 3, 2026. Always run the latest patch to benefit from all security fixes.
How to migrate from Fluent Bit 4 to Fluent Bit 5?
To migrate from Fluent Bit 4 to Fluent Bit 5: (1) review the official Fluent Bit 5 migration guide for breaking changes, (2) update dependencies and configuration accordingly, (3) test thoroughly in a staging environment, (4) deploy with a rollback plan. Starting early gives you time to resolve compatibility issues before your current version reaches end of life.
Is it safe to run Fluent Bit 4 in production?
Fluent Bit 4 is still supported and safe for production use until June 30, 2026. Ensure you are running the latest patch version (4.2.5) to have all security fixes applied.
Data sourced from endoflife.date · CVE data from NVD · EPSS from FIRST.org · KEV from CISA