# CVE-2026-4819: floragunn Search Guard FLX credential leakage in audit logs

Source: https://junglewise.ai/threats/cve-2026-4819-floragunn-search-guard-flx-credential-leakage-in-audit-logs  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-03-31. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2026-4819 · Severity: medium · CVSS 4.9 · Published 2026-03-31

Search Guard FLX, a security plugin for Elasticsearch and Kibana, contains a vulnerability where user login credentials may be inadvertently recorded in audit logs. If an unauthorized person gains access to these log files, they could obtain plain-text passwords, leading to account takeovers and unauthorized access to sensitive data. This issue affects organizations using the audit logging feature during Kibana login events.

Technologies: [Floragunn Search Guard FLX](https://junglewise.ai/threats/technologies/search-guard-flx), [Search-Guard Flx](https://junglewise.ai/threats/technologies/flx). Vendors: [Floragunn](https://junglewise.ai/threats/vendors/floragunn), [Search-Guard](https://junglewise.ai/threats/vendors/search-guard).

## Quick answers

**Is CVE-2026-4819 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-4819 being exploited in the wild.

**How severe is CVE-2026-4819?** Medium severity, with a CVSS score of 4.9, published 31 March 2026.

**Which products and versions are affected?** Floragunn Search Guard FLX 1.0.0 - 4.0.1.

**Is there a fix for CVE-2026-4819?** A patch was published on 2026-03-25: Version 4.1.0 released. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-4819 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-4819?** Check whether you run Floragunn Search Guard FLX or Search-Guard Flx at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A vulnerability in the audit logging feature of Search Guard FLX (versions 1.0.0 to 4.0.1) can lead to the insertion of sensitive information into log files (CWE-532). Specifically, when users log into Kibana, the audit log may capture the request body containing plain-text credentials. An attacker with access to the audit logs—typically requiring high privileges or local access—could retrieve these credentials to impersonate users. The issue is rooted in the KIBANA_LOGIN and KIBANA_LOGOUT event handling. A fix is available in version 4.1.0, which properly excludes sensitive headers and provides more granular control over request-body logging. Temporary mitigations include disabling request-body logging globally or specifically for the authentication session path.

## Affected products

- floragunn Search Guard FLX 1.0.0 - 4.0.1

## Timeline

- 2026-03-25: patched: Version 4.1.0 released.
- 2026-03-31: disclosed: Initial advisory publication.
- 2026-03-31: advisory: NVD entry published.

## References

- [https://docs.search-guard.com/latest/changelog-searchguard-flx-4_1_0](https://docs.search-guard.com/latest/changelog-searchguard-flx-4_1_0)
- [https://search-guard.com/cve-advisory/](https://search-guard.com/cve-advisory/)

## Related threats

- [floragunn Search Guard FLX improper authorization in data stream management](https://junglewise.ai/threats/cve-2026-4818-floragunn-search-guard-flx-improper-authorization-in-data-stream)
- [floragunn Search Guard FLX open redirect in Kibana Plugin](https://junglewise.ai/threats/cve-2026-4799-floragunn-search-guard-flx-open-redirect-in-kibana-plugin)