What is CVE-2026-63263?

CVE-2026-63263 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2026-07-22.

How severe is CVE-2026-63263?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Resource exhaustion in Elastic Elasticsearch

CVE-2026-63263

Uncontrolled Resource Consumption (CWE-400) in Elasticsearch can lead to denial of service via Exponential Data Expansion (CAPEC-197). An authenticated user may submit a specially crafted query to the ES|QL engine that causes exponential C…

Vulnerability class: DoS (Denial of Service)

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Elastic Elasticsearch — versions 9.4.0, 9.0.0, 8.0.0

Weakness classification (CWE)

CWE-400 — Uncontrolled Resource Consumption

References

security@elastic.co

Frequently asked questions

What is CVE-2026-63263?: CVE-2026-63263 is a medium-severity vulnerability in Elastic Elasticsearch, classified under Uncontrolled Resource Consumption. CVSS score: 6.5/10. Published 2026-07-22.
How severe is CVE-2026-63263?: Medium severity. CVSS v3 base score is 6.5 out of 10.