### Elasticsearch Version
9.4.0
### Installed Plugins
_No response_
### Java… Version
openjdk version "21.0.11" 2026-04-21
### OS Version
Linux tlog-server 6.12.85+deb13-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.85-1 (2026-04-30) x86_64 GNU/Linux
### Problem Description
After running `apt update && apt upgrade --yes` on my Debian machine, I upgraded my ELK stack from 9.3.4 to 9.4.0:
```
00:01:31.910 Unpacking elasticsearch (9.4.0) over (9.3.4) ...
00:01:43.104 Unpacking kibana (9.4.0) over (9.3.4) ...
00:02:39.370 Unpacking logstash (1:9.4.0-1) over (1:9.3.4-1) ...
00:03:00.231 Unpacking metricbeat (9.4.0) over (9.3.4) ...
```
From that point kibana, logstash and metricbeat worked - while elasticsearch failed to start. `systemctl status elasticsearch` produced:
```
The current machine does not support all of the following CPU features that are required by the image: [CX8, CMOV, FXSR, MMX, SSE, SSE2, SSE3, SSSE3, SSE4_1, SSE4_2,>
Please rebuild the executable with an appropriate setting of the -march option.
```
From inspecting `/proc/cpuinfo` It seems my machine does support all of the above flags - BUT `SSE3` is listed as `pni` ([Prescott New Instructions](https://en.wikipedia.org/wiki/SSE3) - Intel's name for `SSE3`).
No matter what I try, I cannot get it to run. What am I missing? I suppose this is the upgrade that happened today to 9.4.0 that made the difference - but I'm not sure why :((
### Steps to Reproduce
Running this command shows how the elasticsearch/logstash JDK versions are different from some reason:
```bash
for prog in elasticsearch kibana logstash metricbeat; do
echo "PROGRAM=${prog}"
$(find /usr/share/${prog} -name java -type f -executable) --version 2>/dev/null || $(find /usr/share/${prog} -name ${prog} -type f -executable) version
echo
done
PROGRAM=elasticsearch
openjdk 26.0.1 2026-04-21
OpenJDK Runtime Environment (build 26.0.1+8-34)
OpenJDK 64-Bit Server VM (build 26.0.1+8-34, mixed mode, sharing)
PROGRAM=kibana
{"log.level":"info","@timestamp":"2026-05-05T14:11:51.336Z","log.logger":"elastic-apm-node","ecs.version":"8.10.0","agentVersion":"4.15.0","env":{"pid":1781,"proctitle":"/usr/share/kibana/bin/../node/default/bin/node","os":"linux 6.12.85+deb13-amd64","arch":"x64","host":"tlog-server","timezone":"UTC+00","runtime":"Node.js v24.14.1"},"config":{"active":{"source":"start","value":true},"breakdownMetrics":{"source":"start","value":false},"captureBody":{"source":"start","value":"off","commonName":"capture_body"},"captureHeaders":{"source":"start","value":false},"centralConfig":{"source":"start","value":false},"contextPropagationOnly":{"source":"start","value":true},"environment":{"source":"start","value":"production"},"globalLabels":{"source":"start","value":[["kibana_uuid","6a99a60b-af9e-40e9-8d36-3a09771fce0a"],["git_rev","b2e39752e03b56f48f51943214475ddba1f8e974"]],"sourceValue":{"kibana_uuid":"6a99a60b-af9e-40e9-8d36-3a09771fce0a","git_rev":"b2e39752e03b56f48f51943214475ddba1f8e974"}},"logLevel":{"source":"default","value":"info","commonName":"log_level"},"metricsInterval":{"source":"start","value":120,"sourceValue":"120s"},"serverUrl":{"source":"start","value":"https://kibana-cloud-apm.apm.us-east-1.aws.found.io/","commonName":"server_url"},"transactionSampleRate":{"source":"start","value":0.1,"commonName":"transaction_sample_rate"},"captureSpanStackTraces":{"source":"start","sourceValue":false},"secretToken":{"source":"start","value":"[REDACTED]","commonName":"secret_token"},"serviceName":{"source":"start","value":"kibana","commonName":"service_name"},"serviceVersion":{"source":"start","value":"9.4.0","commonName":"service_version"}},"activationMethod":"require","message":"Elastic APM Node.js Agent v4.15.0"}
Kibana should not be run as root. Use --allow-root to continue.
PROGRAM=logstash
openjdk 21.0.10 2026-01-20 LTS
OpenJDK Runtime Environment Temurin-21.0.10+7 (build 21.0.10+7-LTS)
OpenJDK 64-Bit Server VM Temurin-21.0.10+7 (build 21.0.10+7-LTS, mixed mode, sharing)
PROGRAM=metricbeat
metricbeat version 9.4.0 (amd64), libbeat 9.4.0 [b988690b1bd5ae02f00c3facb413d4ee758563fe built 2026-04-30 13:28:43 +0000 UTC] (FIPS-distribution: false)
```
### Logs (if relevant)
_No response_
the pull request is merged for the next release.