CVE-2026-94408: Elastic Elasticsearch denial of service via resource exhaustion

CVE-2026-94408 · Severity: medium · CVSS 4.9 · Published 2026-09-26

Elasticsearch, a widely used search and analytics engine, contains a vulnerability that allows attackers with administrative privileges to exhaust system resources and cause a denial of service. An attacker could trigger excessive memory or CPU allocation on Elasticsearch clusters, making the search and analytics service unavailable to legitimate users and potentially disrupting dependent applications and data pipelines.

Technologies: Elasticsearch. Vendors: Elastic.

Quick answers

Is CVE-2026-94408 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-94408 being exploited in the wild.
How severe is CVE-2026-94408?
Medium severity, with a CVSS score of 4.9, published 26 September 2026.
Which products and versions are affected?
Elasticsearch 8.0.0 through 8.19.21, 9.0.0 through 9.4.6, 9.5.0 through 9.5.2.
Is there a fix for CVE-2026-94408?
A patch was published on 2026-09-26: Fixed in Elasticsearch 8.19.22, 9.4.7, 9.5.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-94408 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-94408?
Check whether you run Elasticsearch 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

Uncontrolled resource consumption (CWE-400) in Elasticsearch permits denial of service through excessive allocation (CAPEC-130) with network-based attack vectors. The vulnerability requires high-level privileges (PR:H), no user interaction, and affects all configurations. Attackers can consume excessive resources leading to service unavailability; patches are available in versions 8.19.22, 9.4.7, and 9.5.3.

Affected products

  • Elastic Elasticsearch 8.0.0 through 8.19.21, 9.0.0 through 9.4.6, 9.5.0 through 9.5.2

Timeline

  • 2026-09-26: disclosed
  • 2026-09-26: patched: Fixed in Elasticsearch 8.19.22, 9.4.7, 9.5.3

References

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