How to Fix CVE-2026-4819: Search Guard FLX (Bundle Sibling)
*By Sai Kiran Pandrala*
Last verified: 2026-05-25
| Severity | CVSS 4.9, Medium |
|---|---|
| Actively exploited? | No |
| Affected | Floragunn Search Guard FLX (1.0.0 <= 4.0.1) |
| Fixed in | Same patched build as CVE-2026-4799 |
| Type (CWE) | CWE-532 |
CVE-2026-4819 is a sibling vulnerability in the same Floragunn Search Guard FLX advisory bundle as CVE-2026-4799. The same patched build closes every CVE in the bundle, so the remediation procedure for CVE-2026-4819 matches the primary write-up.
What is different about CVE-2026-4819?
In Search Guard FLX versions from 1.0.0 up to 4.0.1, the audit logging feature might log user credentials from users logging into Kibana.
Impact is consistent with the bundle: compromise of the affected component as described in the vendor advisory. The patched build closes every code path in the advisory in one update.
How to fix CVE-2026-4819
Apply the patched build per the primary write-up: How to Fix CVE-2026-4799.
For a quick check, confirm the running version of Search Guard FLX:
# Confirm the installed version via your package manager
dpkg -l | grep -i search # Debian/Ubuntu
rpm -qa | grep -i search # RHEL/CentOS/Rocky
Frequently asked questions
Is CVE-2026-4819 being actively exploited?
Not at the time of writing. It is not listed in CISA's Known Exploited Vulnerabilities catalog. That status can change, so monitor the vendor advisory and the KEV catalog if the system is exposed.
How severe is CVE-2026-4819?
CVSS rates it 4.9 (Medium). Use that score to set your patch priority alongside the other items in your queue.
Do I have to take Search Guard FLX offline to apply the patch?
It depends on the deployment. High-availability or clustered installs can usually patch one node at a time with no full outage. Standalone installs typically need a short restart. Always follow the vendor's documented upgrade steps.
What if my vulnerability scanner still flags CVE-2026-4819 after I patch?
Re-run the scan after a service restart, then confirm the scanner's plugin set is up to date. Some scanners detect by banner version only and lag the official fix metadata by a release.
References
- Official vendor advisory: https://search-guard.com/cve-advisory/
- NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2026-4819
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Primary write-up: How to Fix CVE-2026-4799
*Written by Sai Kiran Pandrala. Last verified 2026-05-25. Part of the Floragunn Search Guard FLX advisory bundle. Full procedure at how-to-fix-cve-2026-4799.*