Apache Solr 8 end of life
Apache Solr 8 reached end of life on 25 October 2024, with 8.11.4 as its final release. Upstream maintains the 9.x line alongside Solr 10, released 3 March 2026, and backports nothing below 9. Solr 8 deployments therefore receive no further security fixes.
- End of life
- 25 October 2024
- Released
- Mar 2019
- Final release
- 8.11.4
- Successor
- Solr 9 or Solr 10
Date published by Apache Solr release history, cross-checked against endoflife.date. We do not publish a lifecycle date we cannot source.
What actually stops on 25 October 2024
- Security fixes for the 8.x line, including the bundled Lucene, Jetty and ZooKeeper client
- Any further 8.x releases — 8.11.4 was the last
- Compatibility work for newer JVMs
What actually breaks in the upgrade
A Solr upgrade is a reindex plus a relevance regression
Lucene index formats change between majors, analysers are deprecated, and query parser behaviour shifts in ways that move result ordering. The binary swap is the easy part; re-validating that search quality did not change is the project, and it needs sign-off from whoever owns relevance.
Solr 10 raised the Java baseline
Solr 10 requires Java 21. For estates still on Java 8 or 11 that is a second migration wearing the first one's clothes, which is why Solr 9 is usually the realistic destination from 8.
Your options, costed honestly
Including the ones that do not involve buying anything from us.
| Option | What it is | Effort | Cost | Our view |
|---|---|---|---|---|
| Upgrade to Solr 9 | The realistic destination from 8.x. | Reindex plus relevance regression | Engineering time and a search-quality sign-off | Correct, and usually a quarter of work rather than a sprint. |
| Jump to Solr 10 | Current line, released 3 March 2026. | Reindex, relevance regression, plus a Java 21 move | Higher | Right if you were moving the JVM anyway. Two migrations at once otherwise. |
| OSSeva extended support | Patched 8.x builds, index format unchanged. | Drop-in — no reindex | Per cluster | Closes the security gap now so the reindex can be scheduled rather than forced. |
What OSSeva does for Apache Solr 8
OSSeva patches this line
OSSeva ships patched Solr 6.x, 7.x and 8.x builds with the Lucene index format unchanged, so patched binaries drop onto the existing data directory. The bundled dependency set is patched too, which is where most Solr advisories actually originate.
Apache Solr extended supportWhat your auditor will say
Search clusters frequently index cardholder-adjacent data for internal tooling. An unpatched Solr node in that path is in scope, and Solr's advisory history is dominated by remote code execution reached through request handlers.
Solr is often deployed on an assumption of network isolation that no longer matches how the application reaches it. Both the access-control and the remediation criteria bite here.
Apache Solr 8: common questions
When did Apache Solr 8 reach end of life?
25 October 2024, with 8.11.4 as the final release. Solr 7 ended on 11 May 2022 and Solr 6 on 13 March 2019.
Can we patch Solr 8 without reindexing?
Yes. Backported builds keep the Lucene index format and analyser behaviour of the release you are on, so they drop onto the same data directory. A reindex is only required when moving to a new major version.
Where do Solr vulnerabilities usually come from?
Two places. Solr's own request handlers — the config API, the historic VelocityResponseWriter and DataImportHandler paths, and the streaming expression handlers — which have produced repeated remote code execution advisories. And the bundled libraries: Lucene, Jetty, the ZooKeeper client and logging. Community backports on an EOL line rarely cover the second.
Still running Apache Solr 8?
Tell us the versions and the estate size. We will tell you honestly whether to upgrade or to buy cover — and we say 'upgrade' more often than you would expect.