Resource exhaustion in Elasticsearch - CVE-2026-63263
Published: July 22, 2026
Vulnerability identifier: #VU139144
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63263
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to uncontrolled resource consumption in the ES|QL engine when processing a specially crafted query. A remote user can submit a specially crafted query to cause a denial of service.
This affects deployments where users are able to execute ES|QL queries, and repeated requests can exhaust query worker resources until the node is restarted.
Affected software
Elasticsearch
How to mitigate CVE-2026-63263
Install security update from vendor's website.
Elasticsearch - addressed in versions 8.19.19, 9.3.8, 9.4.4